Annotation of src/usr.bin/ssh/packet.c, Revision 1.309.4.1
1.309.4.1! bluhm 1: /* $OpenBSD: packet.c,v 1.309 2023/03/03 10:23:42 dtucker Exp $ */
1.1 deraadt 2: /*
1.15 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.35 deraadt 6: * This file contains code implementing the packet protocol and communication
7: * with the other side. This same code is used both on client and server side.
1.29 markus 8: *
1.35 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
1.29 markus 14: *
1.25 markus 15: *
16: * SSH2 packet format added by Markus Friedl.
1.69 markus 17: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.25 markus 18: *
1.35 deraadt 19: * Redistribution and use in source and binary forms, with or without
20: * modification, are permitted provided that the following conditions
21: * are met:
22: * 1. Redistributions of source code must retain the above copyright
23: * notice, this list of conditions and the following disclaimer.
24: * 2. Redistributions in binary form must reproduce the above copyright
25: * notice, this list of conditions and the following disclaimer in the
26: * documentation and/or other materials provided with the distribution.
27: *
28: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
29: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
30: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
31: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
32: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
33: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
37: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.15 deraadt 38: */
1.1 deraadt 39:
1.142 deraadt 40: #include <sys/types.h>
1.105 markus 41: #include <sys/queue.h>
1.132 stevesk 42: #include <sys/socket.h>
1.138 stevesk 43: #include <sys/time.h>
1.132 stevesk 44: #include <netinet/in.h>
1.121 stevesk 45: #include <netinet/ip.h>
1.134 stevesk 46:
1.135 stevesk 47: #include <errno.h>
1.230 djm 48: #include <netdb.h>
1.134 stevesk 49: #include <stdarg.h>
1.141 stevesk 50: #include <stdio.h>
1.140 stevesk 51: #include <stdlib.h>
1.137 stevesk 52: #include <string.h>
1.136 stevesk 53: #include <unistd.h>
1.203 deraadt 54: #include <limits.h>
1.278 djm 55: #include <poll.h>
1.142 deraadt 56: #include <signal.h>
1.184 dtucker 57: #include <time.h>
1.1 deraadt 58:
1.288 dtucker 59: #ifdef WITH_ZLIB
1.201 markus 60: #include <zlib.h>
1.288 dtucker 61: #endif
1.201 markus 62:
1.1 deraadt 63: #include "xmalloc.h"
1.25 markus 64: #include "compat.h"
65: #include "ssh2.h"
1.37 markus 66: #include "cipher.h"
1.201 markus 67: #include "sshkey.h"
1.25 markus 68: #include "kex.h"
1.200 markus 69: #include "digest.h"
1.50 markus 70: #include "mac.h"
1.46 markus 71: #include "log.h"
72: #include "canohost.h"
1.87 stevesk 73: #include "misc.h"
1.198 millert 74: #include "channels.h"
1.95 markus 75: #include "ssh.h"
1.201 markus 76: #include "packet.h"
1.197 djm 77: #include "ssherr.h"
1.201 markus 78: #include "sshbuf.h"
1.25 markus 79:
80: #ifdef PACKET_DEBUG
81: #define DBG(x) x
82: #else
83: #define DBG(x)
84: #endif
85:
1.159 markus 86: #define PACKET_MAX_SIZE (256 * 1024)
87:
1.161 andreas 88: struct packet_state {
89: u_int32_t seqnr;
90: u_int32_t packets;
91: u_int64_t blocks;
92: u_int64_t bytes;
93: };
94:
95: struct packet {
96: TAILQ_ENTRY(packet) next;
97: u_char type;
1.201 markus 98: struct sshbuf *payload;
1.161 andreas 99: };
100:
101: struct session_state {
102: /*
103: * This variable contains the file descriptors used for
104: * communicating with the other side. connection_in is used for
105: * reading; connection_out for writing. These can be the same
106: * descriptor, in which case it is assumed to be a socket.
107: */
108: int connection_in;
109: int connection_out;
110:
111: /* Protocol flags for the remote side. */
112: u_int remote_protocol_flags;
1.1 deraadt 113:
1.161 andreas 114: /* Encryption context for receiving data. Only used for decryption. */
1.235 djm 115: struct sshcipher_ctx *receive_context;
1.1 deraadt 116:
1.161 andreas 117: /* Encryption context for sending data. Only used for encryption. */
1.235 djm 118: struct sshcipher_ctx *send_context;
1.14 markus 119:
1.161 andreas 120: /* Buffer for raw input data from the socket. */
1.201 markus 121: struct sshbuf *input;
1.1 deraadt 122:
1.161 andreas 123: /* Buffer for raw output data going to the socket. */
1.201 markus 124: struct sshbuf *output;
1.1 deraadt 125:
1.161 andreas 126: /* Buffer for the partial outgoing packet being constructed. */
1.201 markus 127: struct sshbuf *outgoing_packet;
1.1 deraadt 128:
1.161 andreas 129: /* Buffer for the incoming packet currently being processed. */
1.201 markus 130: struct sshbuf *incoming_packet;
1.1 deraadt 131:
1.161 andreas 132: /* Scratch buffer for packet compression/decompression. */
1.201 markus 133: struct sshbuf *compression_buffer;
134:
1.288 dtucker 135: #ifdef WITH_ZLIB
1.201 markus 136: /* Incoming/outgoing compression dictionaries */
137: z_stream compression_in_stream;
138: z_stream compression_out_stream;
1.288 dtucker 139: #endif
1.201 markus 140: int compression_in_started;
141: int compression_out_started;
142: int compression_in_failures;
143: int compression_out_failures;
1.1 deraadt 144:
1.161 andreas 145: /* default maximum packet size */
146: u_int max_packet_size;
1.1 deraadt 147:
1.161 andreas 148: /* Flag indicating whether this module has been initialized. */
149: int initialized;
1.12 markus 150:
1.161 andreas 151: /* Set to true if the connection is interactive. */
152: int interactive_mode;
1.1 deraadt 153:
1.161 andreas 154: /* Set to true if we are the server side. */
155: int server_side;
1.1 deraadt 156:
1.161 andreas 157: /* Set to true if we are authenticated. */
158: int after_authentication;
1.118 markus 159:
1.161 andreas 160: int keep_alive_timeouts;
1.118 markus 161:
1.161 andreas 162: /* The maximum time that we will wait to send or receive a packet */
163: int packet_timeout_ms;
1.151 dtucker 164:
1.161 andreas 165: /* Session key information for Encryption and MAC */
1.201 markus 166: struct newkeys *newkeys[MODE_MAX];
1.161 andreas 167: struct packet_state p_read, p_send;
1.154 dtucker 168:
1.184 dtucker 169: /* Volume-based rekeying */
1.224 dtucker 170: u_int64_t max_blocks_in, max_blocks_out, rekey_limit;
1.105 markus 171:
1.184 dtucker 172: /* Time-based rekeying */
1.208 markus 173: u_int32_t rekey_interval; /* how often in seconds */
1.184 dtucker 174: time_t rekey_time; /* time of last rekeying */
175:
1.161 andreas 176: /* roundup current message to extra_pad bytes */
177: u_char extra_pad;
1.95 markus 178:
1.161 andreas 179: /* XXX discard incoming data after MAC error */
180: u_int packet_discard;
1.234 markus 181: size_t packet_discard_mac_already;
1.201 markus 182: struct sshmac *packet_discard_mac;
1.71 markus 183:
1.161 andreas 184: /* Used in packet_read_poll2() */
185: u_int packlen;
1.159 markus 186:
1.165 andreas 187: /* Used in packet_send2 */
188: int rekeying;
189:
1.242 markus 190: /* Used in ssh_packet_send_mux() */
191: int mux;
192:
1.165 andreas 193: /* Used in packet_set_interactive */
194: int set_interactive_called;
195:
196: /* Used in packet_set_maxsize */
197: int set_maxsize_called;
198:
1.201 markus 199: /* One-off warning about weak ciphers */
200: int cipher_warning_done;
201:
1.243 djm 202: /* Hook for fuzzing inbound packets */
203: ssh_packet_hook_fn *hook_in;
204: void *hook_in_ctx;
205:
1.161 andreas 206: TAILQ_HEAD(, packet) outgoing;
1.105 markus 207: };
1.161 andreas 208:
1.201 markus 209: struct ssh *
210: ssh_alloc_session_state(void)
1.161 andreas 211: {
1.201 markus 212: struct ssh *ssh = NULL;
213: struct session_state *state = NULL;
1.161 andreas 214:
1.201 markus 215: if ((ssh = calloc(1, sizeof(*ssh))) == NULL ||
216: (state = calloc(1, sizeof(*state))) == NULL ||
1.278 djm 217: (ssh->kex = kex_new()) == NULL ||
1.201 markus 218: (state->input = sshbuf_new()) == NULL ||
219: (state->output = sshbuf_new()) == NULL ||
220: (state->outgoing_packet = sshbuf_new()) == NULL ||
221: (state->incoming_packet = sshbuf_new()) == NULL)
222: goto fail;
223: TAILQ_INIT(&state->outgoing);
1.202 markus 224: TAILQ_INIT(&ssh->private_keys);
225: TAILQ_INIT(&ssh->public_keys);
1.201 markus 226: state->connection_in = -1;
227: state->connection_out = -1;
228: state->max_packet_size = 32768;
229: state->packet_timeout_ms = -1;
230: state->p_send.packets = state->p_read.packets = 0;
231: state->initialized = 1;
232: /*
233: * ssh_packet_send2() needs to queue packets until
234: * we've done the initial key exchange.
235: */
236: state->rekeying = 1;
237: ssh->state = state;
238: return ssh;
239: fail:
1.278 djm 240: if (ssh) {
241: kex_free(ssh->kex);
242: free(ssh);
243: }
1.201 markus 244: if (state) {
245: sshbuf_free(state->input);
246: sshbuf_free(state->output);
247: sshbuf_free(state->incoming_packet);
248: sshbuf_free(state->outgoing_packet);
249: free(state);
250: }
251: return NULL;
1.161 andreas 252: }
1.105 markus 253:
1.243 djm 254: void
255: ssh_packet_set_input_hook(struct ssh *ssh, ssh_packet_hook_fn *hook, void *ctx)
256: {
257: ssh->state->hook_in = hook;
258: ssh->state->hook_in_ctx = ctx;
259: }
260:
1.228 djm 261: /* Returns nonzero if rekeying is in progress */
262: int
263: ssh_packet_is_rekeying(struct ssh *ssh)
264: {
1.292 markus 265: return ssh->state->rekeying ||
266: (ssh->kex != NULL && ssh->kex->done == 0);
1.228 djm 267: }
268:
1.16 markus 269: /*
1.253 naddy 270: * Sets the descriptors used for communication.
1.16 markus 271: */
1.201 markus 272: struct ssh *
273: ssh_packet_set_connection(struct ssh *ssh, int fd_in, int fd_out)
1.1 deraadt 274: {
1.201 markus 275: struct session_state *state;
276: const struct sshcipher *none = cipher_by_name("none");
1.197 djm 277: int r;
1.97 deraadt 278:
1.205 djm 279: if (none == NULL) {
1.297 djm 280: error_f("cannot load cipher 'none'");
1.205 djm 281: return NULL;
282: }
1.201 markus 283: if (ssh == NULL)
284: ssh = ssh_alloc_session_state();
1.205 djm 285: if (ssh == NULL) {
1.297 djm 286: error_f("could not allocate state");
1.205 djm 287: return NULL;
288: }
1.201 markus 289: state = ssh->state;
290: state->connection_in = fd_in;
291: state->connection_out = fd_out;
292: if ((r = cipher_init(&state->send_context, none,
1.197 djm 293: (const u_char *)"", 0, NULL, 0, CIPHER_ENCRYPT)) != 0 ||
1.201 markus 294: (r = cipher_init(&state->receive_context, none,
1.205 djm 295: (const u_char *)"", 0, NULL, 0, CIPHER_DECRYPT)) != 0) {
1.297 djm 296: error_fr(r, "cipher_init failed");
1.230 djm 297: free(ssh); /* XXX need ssh_free_session_state? */
1.205 djm 298: return NULL;
299: }
1.201 markus 300: state->newkeys[MODE_IN] = state->newkeys[MODE_OUT] = NULL;
1.207 djm 301: /*
302: * Cache the IP address of the remote connection for use in error
303: * messages that might be generated after the connection has closed.
304: */
305: (void)ssh_remote_ipaddr(ssh);
1.201 markus 306: return ssh;
1.1 deraadt 307: }
308:
1.154 dtucker 309: void
1.201 markus 310: ssh_packet_set_timeout(struct ssh *ssh, int timeout, int count)
1.154 dtucker 311: {
1.201 markus 312: struct session_state *state = ssh->state;
313:
1.174 djm 314: if (timeout <= 0 || count <= 0) {
1.201 markus 315: state->packet_timeout_ms = -1;
1.154 dtucker 316: return;
317: }
318: if ((INT_MAX / 1000) / count < timeout)
1.201 markus 319: state->packet_timeout_ms = INT_MAX;
1.154 dtucker 320: else
1.201 markus 321: state->packet_timeout_ms = timeout * count * 1000;
1.154 dtucker 322: }
323:
1.242 markus 324: void
325: ssh_packet_set_mux(struct ssh *ssh)
326: {
327: ssh->state->mux = 1;
328: ssh->state->rekeying = 0;
1.292 markus 329: kex_free(ssh->kex);
330: ssh->kex = NULL;
1.242 markus 331: }
332:
333: int
334: ssh_packet_get_mux(struct ssh *ssh)
335: {
336: return ssh->state->mux;
337: }
338:
1.201 markus 339: int
1.245 djm 340: ssh_packet_set_log_preamble(struct ssh *ssh, const char *fmt, ...)
341: {
342: va_list args;
343: int r;
344:
345: free(ssh->log_preamble);
346: if (fmt == NULL)
347: ssh->log_preamble = NULL;
348: else {
349: va_start(args, fmt);
350: r = vasprintf(&ssh->log_preamble, fmt, args);
351: va_end(args);
352: if (r < 0 || ssh->log_preamble == NULL)
353: return SSH_ERR_ALLOC_FAIL;
354: }
355: return 0;
356: }
357:
358: int
1.201 markus 359: ssh_packet_stop_discard(struct ssh *ssh)
1.159 markus 360: {
1.201 markus 361: struct session_state *state = ssh->state;
362: int r;
363:
364: if (state->packet_discard_mac) {
1.159 markus 365: char buf[1024];
1.234 markus 366: size_t dlen = PACKET_MAX_SIZE;
1.201 markus 367:
1.234 markus 368: if (dlen > state->packet_discard_mac_already)
369: dlen -= state->packet_discard_mac_already;
1.159 markus 370: memset(buf, 'a', sizeof(buf));
1.234 markus 371: while (sshbuf_len(state->incoming_packet) < dlen)
1.201 markus 372: if ((r = sshbuf_put(state->incoming_packet, buf,
373: sizeof(buf))) != 0)
374: return r;
375: (void) mac_compute(state->packet_discard_mac,
376: state->p_read.seqnr,
1.234 markus 377: sshbuf_ptr(state->incoming_packet), dlen,
1.201 markus 378: NULL, 0);
1.159 markus 379: }
1.220 djm 380: logit("Finished discarding for %.200s port %d",
381: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.201 markus 382: return SSH_ERR_MAC_INVALID;
1.159 markus 383: }
384:
1.201 markus 385: static int
386: ssh_packet_start_discard(struct ssh *ssh, struct sshenc *enc,
1.234 markus 387: struct sshmac *mac, size_t mac_already, u_int discard)
1.159 markus 388: {
1.201 markus 389: struct session_state *state = ssh->state;
390: int r;
391:
392: if (enc == NULL || !cipher_is_cbc(enc->cipher) || (mac && mac->etm)) {
393: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
394: return r;
395: return SSH_ERR_MAC_INVALID;
396: }
1.234 markus 397: /*
398: * Record number of bytes over which the mac has already
399: * been computed in order to minimize timing attacks.
400: */
401: if (mac && mac->enabled) {
1.201 markus 402: state->packet_discard_mac = mac;
1.234 markus 403: state->packet_discard_mac_already = mac_already;
404: }
405: if (sshbuf_len(state->input) >= discard)
406: return ssh_packet_stop_discard(ssh);
1.201 markus 407: state->packet_discard = discard - sshbuf_len(state->input);
408: return 0;
1.159 markus 409: }
410:
1.19 markus 411: /* Returns 1 if remote host is connected via socket, 0 if not. */
412:
413: int
1.201 markus 414: ssh_packet_connection_is_on_socket(struct ssh *ssh)
1.19 markus 415: {
1.271 djm 416: struct session_state *state;
1.19 markus 417: struct sockaddr_storage from, to;
418: socklen_t fromlen, tolen;
419:
1.271 djm 420: if (ssh == NULL || ssh->state == NULL)
421: return 0;
422:
423: state = ssh->state;
1.230 djm 424: if (state->connection_in == -1 || state->connection_out == -1)
425: return 0;
1.19 markus 426: /* filedescriptors in and out are the same, so it's a socket */
1.201 markus 427: if (state->connection_in == state->connection_out)
1.19 markus 428: return 1;
429: fromlen = sizeof(from);
430: memset(&from, 0, sizeof(from));
1.201 markus 431: if (getpeername(state->connection_in, (struct sockaddr *)&from,
1.286 deraadt 432: &fromlen) == -1)
1.19 markus 433: return 0;
434: tolen = sizeof(to);
435: memset(&to, 0, sizeof(to));
1.201 markus 436: if (getpeername(state->connection_out, (struct sockaddr *)&to,
1.286 deraadt 437: &tolen) == -1)
1.19 markus 438: return 0;
439: if (fromlen != tolen || memcmp(&from, &to, fromlen) != 0)
440: return 0;
441: if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
442: return 0;
443: return 1;
444: }
445:
1.91 markus 446: void
1.201 markus 447: ssh_packet_get_bytes(struct ssh *ssh, u_int64_t *ibytes, u_int64_t *obytes)
1.91 markus 448: {
1.201 markus 449: if (ibytes)
450: *ibytes = ssh->state->p_read.bytes;
451: if (obytes)
452: *obytes = ssh->state->p_send.bytes;
1.91 markus 453: }
1.125 deraadt 454:
1.91 markus 455: int
1.201 markus 456: ssh_packet_connection_af(struct ssh *ssh)
1.19 markus 457: {
1.298 djm 458: return get_sock_af(ssh->state->connection_out);
1.19 markus 459: }
460:
1.1 deraadt 461: /* Sets the connection into non-blocking mode. */
462:
1.2 provos 463: void
1.201 markus 464: ssh_packet_set_nonblocking(struct ssh *ssh)
1.1 deraadt 465: {
1.14 markus 466: /* Set the socket into non-blocking mode. */
1.201 markus 467: set_nonblock(ssh->state->connection_in);
1.14 markus 468:
1.201 markus 469: if (ssh->state->connection_out != ssh->state->connection_in)
470: set_nonblock(ssh->state->connection_out);
1.1 deraadt 471: }
472:
473: /* Returns the socket used for reading. */
474:
1.2 provos 475: int
1.201 markus 476: ssh_packet_get_connection_in(struct ssh *ssh)
1.1 deraadt 477: {
1.201 markus 478: return ssh->state->connection_in;
1.1 deraadt 479: }
480:
481: /* Returns the descriptor used for writing. */
482:
1.2 provos 483: int
1.201 markus 484: ssh_packet_get_connection_out(struct ssh *ssh)
1.1 deraadt 485: {
1.201 markus 486: return ssh->state->connection_out;
487: }
488:
489: /*
490: * Returns the IP-address of the remote host as a string. The returned
491: * string must not be freed.
492: */
493:
494: const char *
495: ssh_remote_ipaddr(struct ssh *ssh)
496: {
1.271 djm 497: int sock;
1.220 djm 498:
1.201 markus 499: /* Check whether we have cached the ipaddr. */
1.220 djm 500: if (ssh->remote_ipaddr == NULL) {
501: if (ssh_packet_connection_is_on_socket(ssh)) {
1.271 djm 502: sock = ssh->state->connection_in;
1.220 djm 503: ssh->remote_ipaddr = get_peer_ipaddr(sock);
1.230 djm 504: ssh->remote_port = get_peer_port(sock);
505: ssh->local_ipaddr = get_local_ipaddr(sock);
506: ssh->local_port = get_local_port(sock);
1.220 djm 507: } else {
1.287 tobhe 508: ssh->remote_ipaddr = xstrdup("UNKNOWN");
1.230 djm 509: ssh->remote_port = 65535;
1.287 tobhe 510: ssh->local_ipaddr = xstrdup("UNKNOWN");
1.230 djm 511: ssh->local_port = 65535;
1.220 djm 512: }
513: }
1.201 markus 514: return ssh->remote_ipaddr;
1.1 deraadt 515: }
516:
1.220 djm 517: /* Returns the port number of the remote host. */
518:
519: int
520: ssh_remote_port(struct ssh *ssh)
521: {
522: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
523: return ssh->remote_port;
1.230 djm 524: }
525:
526: /*
527: * Returns the IP-address of the local host as a string. The returned
528: * string must not be freed.
529: */
530:
531: const char *
532: ssh_local_ipaddr(struct ssh *ssh)
533: {
534: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
535: return ssh->local_ipaddr;
536: }
537:
538: /* Returns the port number of the local host. */
539:
540: int
541: ssh_local_port(struct ssh *ssh)
542: {
543: (void)ssh_remote_ipaddr(ssh); /* Will lookup and cache. */
544: return ssh->local_port;
1.266 djm 545: }
546:
547: /* Returns the routing domain of the input socket, or NULL if unavailable */
548: const char *
549: ssh_packet_rdomain_in(struct ssh *ssh)
550: {
551: if (ssh->rdomain_in != NULL)
552: return ssh->rdomain_in;
553: if (!ssh_packet_connection_is_on_socket(ssh))
554: return NULL;
555: ssh->rdomain_in = get_rdomain(ssh->state->connection_in);
556: return ssh->rdomain_in;
1.220 djm 557: }
558:
1.1 deraadt 559: /* Closes the connection and clears and frees internal data structures. */
560:
1.257 markus 561: static void
562: ssh_packet_close_internal(struct ssh *ssh, int do_close)
1.1 deraadt 563: {
1.201 markus 564: struct session_state *state = ssh->state;
565: u_int mode;
566:
567: if (!state->initialized)
1.14 markus 568: return;
1.201 markus 569: state->initialized = 0;
1.257 markus 570: if (do_close) {
571: if (state->connection_in == state->connection_out) {
572: close(state->connection_out);
573: } else {
574: close(state->connection_in);
575: close(state->connection_out);
576: }
1.14 markus 577: }
1.201 markus 578: sshbuf_free(state->input);
579: sshbuf_free(state->output);
580: sshbuf_free(state->outgoing_packet);
581: sshbuf_free(state->incoming_packet);
1.257 markus 582: for (mode = 0; mode < MODE_MAX; mode++) {
583: kex_free_newkeys(state->newkeys[mode]); /* current keys */
584: state->newkeys[mode] = NULL;
585: ssh_clear_newkeys(ssh, mode); /* next keys */
586: }
1.288 dtucker 587: #ifdef WITH_ZLIB
1.289 dtucker 588: /* compression state is in shared mem, so we can only release it once */
1.257 markus 589: if (do_close && state->compression_buffer) {
1.201 markus 590: sshbuf_free(state->compression_buffer);
591: if (state->compression_out_started) {
592: z_streamp stream = &state->compression_out_stream;
593: debug("compress outgoing: "
594: "raw data %llu, compressed %llu, factor %.2f",
595: (unsigned long long)stream->total_in,
596: (unsigned long long)stream->total_out,
597: stream->total_in == 0 ? 0.0 :
598: (double) stream->total_out / stream->total_in);
599: if (state->compression_out_failures == 0)
600: deflateEnd(stream);
601: }
602: if (state->compression_in_started) {
1.260 dtucker 603: z_streamp stream = &state->compression_in_stream;
1.201 markus 604: debug("compress incoming: "
605: "raw data %llu, compressed %llu, factor %.2f",
606: (unsigned long long)stream->total_out,
607: (unsigned long long)stream->total_in,
608: stream->total_out == 0 ? 0.0 :
609: (double) stream->total_in / stream->total_out);
610: if (state->compression_in_failures == 0)
611: inflateEnd(stream);
612: }
1.14 markus 613: }
1.288 dtucker 614: #endif /* WITH_ZLIB */
1.235 djm 615: cipher_free(state->send_context);
616: cipher_free(state->receive_context);
617: state->send_context = state->receive_context = NULL;
1.257 markus 618: if (do_close) {
1.277 djm 619: free(ssh->local_ipaddr);
620: ssh->local_ipaddr = NULL;
1.257 markus 621: free(ssh->remote_ipaddr);
622: ssh->remote_ipaddr = NULL;
623: free(ssh->state);
624: ssh->state = NULL;
1.295 markus 625: kex_free(ssh->kex);
626: ssh->kex = NULL;
1.257 markus 627: }
628: }
629:
630: void
631: ssh_packet_close(struct ssh *ssh)
632: {
633: ssh_packet_close_internal(ssh, 1);
634: }
635:
636: void
637: ssh_packet_clear_keys(struct ssh *ssh)
638: {
639: ssh_packet_close_internal(ssh, 0);
1.1 deraadt 640: }
641:
642: /* Sets remote side protocol flags. */
643:
1.2 provos 644: void
1.201 markus 645: ssh_packet_set_protocol_flags(struct ssh *ssh, u_int protocol_flags)
1.1 deraadt 646: {
1.201 markus 647: ssh->state->remote_protocol_flags = protocol_flags;
1.1 deraadt 648: }
649:
650: /* Returns the remote protocol flags set earlier by the above function. */
651:
1.40 markus 652: u_int
1.201 markus 653: ssh_packet_get_protocol_flags(struct ssh *ssh)
1.1 deraadt 654: {
1.201 markus 655: return ssh->state->remote_protocol_flags;
1.1 deraadt 656: }
657:
1.16 markus 658: /*
659: * Starts packet compression from the next packet on in both directions.
660: * Level is compression level 1 (fastest) - 9 (slow, best) as in gzip.
661: */
1.1 deraadt 662:
1.201 markus 663: static int
664: ssh_packet_init_compression(struct ssh *ssh)
1.60 markus 665: {
1.201 markus 666: if (!ssh->state->compression_buffer &&
1.300 djm 667: ((ssh->state->compression_buffer = sshbuf_new()) == NULL))
1.201 markus 668: return SSH_ERR_ALLOC_FAIL;
669: return 0;
1.60 markus 670: }
671:
1.288 dtucker 672: #ifdef WITH_ZLIB
1.201 markus 673: static int
674: start_compression_out(struct ssh *ssh, int level)
1.1 deraadt 675: {
1.201 markus 676: if (level < 1 || level > 9)
677: return SSH_ERR_INVALID_ARGUMENT;
678: debug("Enabling compression at level %d.", level);
679: if (ssh->state->compression_out_started == 1)
680: deflateEnd(&ssh->state->compression_out_stream);
681: switch (deflateInit(&ssh->state->compression_out_stream, level)) {
682: case Z_OK:
683: ssh->state->compression_out_started = 1;
684: break;
685: case Z_MEM_ERROR:
686: return SSH_ERR_ALLOC_FAIL;
687: default:
688: return SSH_ERR_INTERNAL_ERROR;
689: }
690: return 0;
1.1 deraadt 691: }
692:
1.201 markus 693: static int
694: start_compression_in(struct ssh *ssh)
695: {
696: if (ssh->state->compression_in_started == 1)
697: inflateEnd(&ssh->state->compression_in_stream);
698: switch (inflateInit(&ssh->state->compression_in_stream)) {
699: case Z_OK:
700: ssh->state->compression_in_started = 1;
701: break;
702: case Z_MEM_ERROR:
703: return SSH_ERR_ALLOC_FAIL;
704: default:
705: return SSH_ERR_INTERNAL_ERROR;
706: }
707: return 0;
1.95 markus 708: }
709:
1.201 markus 710: /* XXX remove need for separate compression buffer */
711: static int
712: compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.95 markus 713: {
1.201 markus 714: u_char buf[4096];
715: int r, status;
716:
717: if (ssh->state->compression_out_started != 1)
718: return SSH_ERR_INTERNAL_ERROR;
719:
720: /* This case is not handled below. */
721: if (sshbuf_len(in) == 0)
722: return 0;
723:
724: /* Input is the contents of the input buffer. */
725: if ((ssh->state->compression_out_stream.next_in =
726: sshbuf_mutable_ptr(in)) == NULL)
727: return SSH_ERR_INTERNAL_ERROR;
728: ssh->state->compression_out_stream.avail_in = sshbuf_len(in);
729:
730: /* Loop compressing until deflate() returns with avail_out != 0. */
731: do {
732: /* Set up fixed-size output buffer. */
733: ssh->state->compression_out_stream.next_out = buf;
734: ssh->state->compression_out_stream.avail_out = sizeof(buf);
735:
736: /* Compress as much data into the buffer as possible. */
737: status = deflate(&ssh->state->compression_out_stream,
738: Z_PARTIAL_FLUSH);
739: switch (status) {
740: case Z_MEM_ERROR:
741: return SSH_ERR_ALLOC_FAIL;
742: case Z_OK:
743: /* Append compressed data to output_buffer. */
744: if ((r = sshbuf_put(out, buf, sizeof(buf) -
745: ssh->state->compression_out_stream.avail_out)) != 0)
746: return r;
747: break;
748: case Z_STREAM_ERROR:
749: default:
750: ssh->state->compression_out_failures++;
751: return SSH_ERR_INVALID_FORMAT;
752: }
753: } while (ssh->state->compression_out_stream.avail_out == 0);
754: return 0;
1.1 deraadt 755: }
756:
1.201 markus 757: static int
758: uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
1.1 deraadt 759: {
1.201 markus 760: u_char buf[4096];
761: int r, status;
1.1 deraadt 762:
1.201 markus 763: if (ssh->state->compression_in_started != 1)
764: return SSH_ERR_INTERNAL_ERROR;
1.25 markus 765:
1.201 markus 766: if ((ssh->state->compression_in_stream.next_in =
767: sshbuf_mutable_ptr(in)) == NULL)
768: return SSH_ERR_INTERNAL_ERROR;
769: ssh->state->compression_in_stream.avail_in = sshbuf_len(in);
1.97 deraadt 770:
1.201 markus 771: for (;;) {
772: /* Set up fixed-size output buffer. */
773: ssh->state->compression_in_stream.next_out = buf;
774: ssh->state->compression_in_stream.avail_out = sizeof(buf);
775:
776: status = inflate(&ssh->state->compression_in_stream,
1.305 djm 777: Z_SYNC_FLUSH);
1.201 markus 778: switch (status) {
779: case Z_OK:
780: if ((r = sshbuf_put(out, buf, sizeof(buf) -
781: ssh->state->compression_in_stream.avail_out)) != 0)
782: return r;
783: break;
784: case Z_BUF_ERROR:
785: /*
786: * Comments in zlib.h say that we should keep calling
787: * inflate() until we get an error. This appears to
788: * be the error that we get.
789: */
790: return 0;
791: case Z_DATA_ERROR:
792: return SSH_ERR_INVALID_FORMAT;
793: case Z_MEM_ERROR:
794: return SSH_ERR_ALLOC_FAIL;
795: case Z_STREAM_ERROR:
796: default:
797: ssh->state->compression_in_failures++;
798: return SSH_ERR_INTERNAL_ERROR;
799: }
800: }
801: /* NOTREACHED */
1.170 djm 802: }
1.288 dtucker 803:
804: #else /* WITH_ZLIB */
805:
806: static int
807: start_compression_out(struct ssh *ssh, int level)
808: {
809: return SSH_ERR_INTERNAL_ERROR;
810: }
811:
812: static int
813: start_compression_in(struct ssh *ssh)
814: {
815: return SSH_ERR_INTERNAL_ERROR;
816: }
817:
818: static int
819: compress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
820: {
821: return SSH_ERR_INTERNAL_ERROR;
822: }
823:
824: static int
825: uncompress_buffer(struct ssh *ssh, struct sshbuf *in, struct sshbuf *out)
826: {
827: return SSH_ERR_INTERNAL_ERROR;
828: }
829: #endif /* WITH_ZLIB */
1.170 djm 830:
1.257 markus 831: void
832: ssh_clear_newkeys(struct ssh *ssh, int mode)
833: {
1.259 djm 834: if (ssh->kex && ssh->kex->newkeys[mode]) {
1.257 markus 835: kex_free_newkeys(ssh->kex->newkeys[mode]);
836: ssh->kex->newkeys[mode] = NULL;
837: }
838: }
839:
1.201 markus 840: int
841: ssh_set_newkeys(struct ssh *ssh, int mode)
1.57 markus 842: {
1.201 markus 843: struct session_state *state = ssh->state;
844: struct sshenc *enc;
845: struct sshmac *mac;
846: struct sshcomp *comp;
1.235 djm 847: struct sshcipher_ctx **ccp;
1.236 markus 848: struct packet_state *ps;
1.105 markus 849: u_int64_t *max_blocks;
1.259 djm 850: const char *wmsg;
1.197 djm 851: int r, crypt_type;
1.283 djm 852: const char *dir = mode == MODE_OUT ? "out" : "in";
1.57 markus 853:
1.303 djm 854: debug2_f("mode %d", mode);
1.57 markus 855:
1.88 markus 856: if (mode == MODE_OUT) {
1.235 djm 857: ccp = &state->send_context;
1.115 avsm 858: crypt_type = CIPHER_ENCRYPT;
1.236 markus 859: ps = &state->p_send;
1.201 markus 860: max_blocks = &state->max_blocks_out;
1.88 markus 861: } else {
1.235 djm 862: ccp = &state->receive_context;
1.115 avsm 863: crypt_type = CIPHER_DECRYPT;
1.236 markus 864: ps = &state->p_read;
1.201 markus 865: max_blocks = &state->max_blocks_in;
1.88 markus 866: }
1.201 markus 867: if (state->newkeys[mode] != NULL) {
1.297 djm 868: debug_f("rekeying %s, input %llu bytes %llu blocks, "
1.300 djm 869: "output %llu bytes %llu blocks", dir,
870: (unsigned long long)state->p_read.bytes,
871: (unsigned long long)state->p_read.blocks,
872: (unsigned long long)state->p_send.bytes,
873: (unsigned long long)state->p_send.blocks);
1.257 markus 874: kex_free_newkeys(state->newkeys[mode]);
875: state->newkeys[mode] = NULL;
1.57 markus 876: }
1.236 markus 877: /* note that both bytes and the seqnr are not reset */
878: ps->packets = ps->blocks = 0;
1.201 markus 879: /* move newkeys from kex to state */
880: if ((state->newkeys[mode] = ssh->kex->newkeys[mode]) == NULL)
881: return SSH_ERR_INTERNAL_ERROR;
882: ssh->kex->newkeys[mode] = NULL;
883: enc = &state->newkeys[mode]->enc;
884: mac = &state->newkeys[mode]->mac;
885: comp = &state->newkeys[mode]->comp;
886: if (cipher_authlen(enc->cipher) == 0) {
887: if ((r = mac_init(mac)) != 0)
888: return r;
889: }
890: mac->enabled = 1;
1.303 djm 891: DBG(debug_f("cipher_init: %s", dir));
1.279 djm 892: cipher_free(*ccp);
893: *ccp = NULL;
1.235 djm 894: if ((r = cipher_init(ccp, enc->cipher, enc->key, enc->key_len,
1.197 djm 895: enc->iv, enc->iv_len, crypt_type)) != 0)
1.201 markus 896: return r;
897: if (!state->cipher_warning_done &&
1.235 djm 898: (wmsg = cipher_warning_message(*ccp)) != NULL) {
1.201 markus 899: error("Warning: %s", wmsg);
900: state->cipher_warning_done = 1;
901: }
1.91 markus 902: /* Deleting the keys does not gain extra security */
1.192 djm 903: /* explicit_bzero(enc->iv, enc->block_size);
904: explicit_bzero(enc->key, enc->key_len);
905: explicit_bzero(mac->key, mac->key_len); */
1.275 sf 906: if ((comp->type == COMP_ZLIB ||
907: (comp->type == COMP_DELAYED &&
1.300 djm 908: state->after_authentication)) && comp->enabled == 0) {
1.201 markus 909: if ((r = ssh_packet_init_compression(ssh)) < 0)
910: return r;
911: if (mode == MODE_OUT) {
912: if ((r = start_compression_out(ssh, 6)) != 0)
913: return r;
914: } else {
915: if ((r = start_compression_in(ssh)) != 0)
916: return r;
917: }
1.57 markus 918: comp->enabled = 1;
919: }
1.109 markus 920: /*
921: * The 2^(blocksize*2) limit is too expensive for 3DES,
1.254 djm 922: * so enforce a 1GB limit for small blocksizes.
1.261 dtucker 923: * See RFC4344 section 3.2.
1.109 markus 924: */
925: if (enc->block_size >= 16)
926: *max_blocks = (u_int64_t)1 << (enc->block_size*2);
927: else
928: *max_blocks = ((u_int64_t)1 << 30) / enc->block_size;
1.201 markus 929: if (state->rekey_limit)
1.237 deraadt 930: *max_blocks = MINIMUM(*max_blocks,
1.201 markus 931: state->rekey_limit / enc->block_size);
1.283 djm 932: debug("rekey %s after %llu blocks", dir,
933: (unsigned long long)*max_blocks);
1.201 markus 934: return 0;
1.57 markus 935: }
936:
1.228 djm 937: #define MAX_PACKETS (1U<<31)
938: static int
939: ssh_packet_need_rekeying(struct ssh *ssh, u_int outbound_packet_len)
940: {
941: struct session_state *state = ssh->state;
942: u_int32_t out_blocks;
943:
944: /* XXX client can't cope with rekeying pre-auth */
945: if (!state->after_authentication)
946: return 0;
947:
948: /* Haven't keyed yet or KEX in progress. */
1.278 djm 949: if (ssh_packet_is_rekeying(ssh))
1.228 djm 950: return 0;
951:
952: /* Peer can't rekey */
953: if (ssh->compat & SSH_BUG_NOREKEY)
954: return 0;
955:
956: /*
957: * Permit one packet in or out per rekey - this allows us to
958: * make progress when rekey limits are very small.
959: */
960: if (state->p_send.packets == 0 && state->p_read.packets == 0)
961: return 0;
962:
963: /* Time-based rekeying */
964: if (state->rekey_interval != 0 &&
1.244 dtucker 965: (int64_t)state->rekey_time + state->rekey_interval <= monotime())
1.228 djm 966: return 1;
967:
1.261 dtucker 968: /*
1.308 djm 969: * Always rekey when MAX_PACKETS sent in either direction
1.261 dtucker 970: * As per RFC4344 section 3.1 we do this after 2^31 packets.
971: */
1.228 djm 972: if (state->p_send.packets > MAX_PACKETS ||
973: state->p_read.packets > MAX_PACKETS)
974: return 1;
975:
1.304 jsg 976: /* Rekey after (cipher-specific) maximum blocks */
1.237 deraadt 977: out_blocks = ROUNDUP(outbound_packet_len,
1.228 djm 978: state->newkeys[MODE_OUT]->enc.block_size);
979: return (state->max_blocks_out &&
980: (state->p_send.blocks + out_blocks > state->max_blocks_out)) ||
981: (state->max_blocks_in &&
982: (state->p_read.blocks > state->max_blocks_in));
983: }
984:
1.301 djm 985: int
986: ssh_packet_check_rekey(struct ssh *ssh)
987: {
988: if (!ssh_packet_need_rekeying(ssh, 0))
989: return 0;
990: debug3_f("rekex triggered");
991: return kex_start_rekex(ssh);
992: }
993:
1.16 markus 994: /*
1.118 markus 995: * Delayed compression for SSH2 is enabled after authentication:
1.143 dtucker 996: * This happens on the server side after a SSH2_MSG_USERAUTH_SUCCESS is sent,
1.118 markus 997: * and on the client side after a SSH2_MSG_USERAUTH_SUCCESS is received.
998: */
1.201 markus 999: static int
1000: ssh_packet_enable_delayed_compress(struct ssh *ssh)
1.118 markus 1001: {
1.201 markus 1002: struct session_state *state = ssh->state;
1003: struct sshcomp *comp = NULL;
1004: int r, mode;
1.118 markus 1005:
1006: /*
1007: * Remember that we are past the authentication step, so rekeying
1.275 sf 1008: * with COMP_DELAYED will turn on compression immediately.
1.118 markus 1009: */
1.201 markus 1010: state->after_authentication = 1;
1.118 markus 1011: for (mode = 0; mode < MODE_MAX; mode++) {
1.145 markus 1012: /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
1.201 markus 1013: if (state->newkeys[mode] == NULL)
1.145 markus 1014: continue;
1.201 markus 1015: comp = &state->newkeys[mode]->comp;
1.275 sf 1016: if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
1.201 markus 1017: if ((r = ssh_packet_init_compression(ssh)) != 0)
1018: return r;
1019: if (mode == MODE_OUT) {
1020: if ((r = start_compression_out(ssh, 6)) != 0)
1021: return r;
1022: } else {
1023: if ((r = start_compression_in(ssh)) != 0)
1024: return r;
1025: }
1.118 markus 1026: comp->enabled = 1;
1027: }
1028: }
1.201 markus 1029: return 0;
1.118 markus 1030: }
1031:
1.226 djm 1032: /* Used to mute debug logging for noisy packet types */
1.242 markus 1033: int
1.226 djm 1034: ssh_packet_log_type(u_char type)
1035: {
1036: switch (type) {
1037: case SSH2_MSG_CHANNEL_DATA:
1038: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1039: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1040: return 0;
1041: default:
1042: return 1;
1043: }
1044: }
1045:
1.118 markus 1046: /*
1.25 markus 1047: * Finalize packet in SSH2 format (compress, mac, encrypt, enqueue)
1048: */
1.201 markus 1049: int
1050: ssh_packet_send2_wrapped(struct ssh *ssh)
1.25 markus 1051: {
1.201 markus 1052: struct session_state *state = ssh->state;
1.200 markus 1053: u_char type, *cp, macbuf[SSH_DIGEST_MAX_LENGTH];
1.233 djm 1054: u_char tmp, padlen, pad = 0;
1.201 markus 1055: u_int authlen = 0, aadlen = 0;
1056: u_int len;
1057: struct sshenc *enc = NULL;
1058: struct sshmac *mac = NULL;
1059: struct sshcomp *comp = NULL;
1060: int r, block_size;
1061:
1062: if (state->newkeys[MODE_OUT] != NULL) {
1063: enc = &state->newkeys[MODE_OUT]->enc;
1064: mac = &state->newkeys[MODE_OUT]->mac;
1065: comp = &state->newkeys[MODE_OUT]->comp;
1.180 markus 1066: /* disable mac for authenticated encryption */
1067: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1068: mac = NULL;
1.25 markus 1069: }
1.88 markus 1070: block_size = enc ? enc->block_size : 8;
1.180 markus 1071: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1072:
1.201 markus 1073: type = (sshbuf_ptr(state->outgoing_packet))[5];
1.226 djm 1074: if (ssh_packet_log_type(type))
1075: debug3("send packet: type %u", type);
1.25 markus 1076: #ifdef PACKET_DEBUG
1077: fprintf(stderr, "plain: ");
1.201 markus 1078: sshbuf_dump(state->outgoing_packet, stderr);
1.25 markus 1079: #endif
1080:
1081: if (comp && comp->enabled) {
1.201 markus 1082: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1083: /* skip header, compress only payload */
1.201 markus 1084: if ((r = sshbuf_consume(state->outgoing_packet, 5)) != 0)
1085: goto out;
1086: sshbuf_reset(state->compression_buffer);
1087: if ((r = compress_buffer(ssh, state->outgoing_packet,
1088: state->compression_buffer)) != 0)
1089: goto out;
1090: sshbuf_reset(state->outgoing_packet);
1091: if ((r = sshbuf_put(state->outgoing_packet,
1092: "\0\0\0\0\0", 5)) != 0 ||
1093: (r = sshbuf_putb(state->outgoing_packet,
1094: state->compression_buffer)) != 0)
1095: goto out;
1096: DBG(debug("compression: raw %d compressed %zd", len,
1097: sshbuf_len(state->outgoing_packet)));
1.25 markus 1098: }
1099:
1100: /* sizeof (packet_len + pad_len + payload) */
1.201 markus 1101: len = sshbuf_len(state->outgoing_packet);
1.25 markus 1102:
1103: /*
1104: * calc size of padding, alloc space, get random data,
1105: * minimum padding is 4 bytes
1106: */
1.178 markus 1107: len -= aadlen; /* packet length is not encrypted for EtM modes */
1.25 markus 1108: padlen = block_size - (len % block_size);
1109: if (padlen < 4)
1110: padlen += block_size;
1.201 markus 1111: if (state->extra_pad) {
1.233 djm 1112: tmp = state->extra_pad;
1.201 markus 1113: state->extra_pad =
1.237 deraadt 1114: ROUNDUP(state->extra_pad, block_size);
1.233 djm 1115: /* check if roundup overflowed */
1116: if (state->extra_pad < tmp)
1117: return SSH_ERR_INVALID_ARGUMENT;
1118: tmp = (len + padlen) % state->extra_pad;
1119: /* Check whether pad calculation below will underflow */
1120: if (tmp > state->extra_pad)
1121: return SSH_ERR_INVALID_ARGUMENT;
1122: pad = state->extra_pad - tmp;
1.297 djm 1123: DBG(debug3_f("adding %d (len %d padlen %d extra_pad %d)",
1124: pad, len, padlen, state->extra_pad));
1.233 djm 1125: tmp = padlen;
1.71 markus 1126: padlen += pad;
1.233 djm 1127: /* Check whether padlen calculation overflowed */
1128: if (padlen < tmp)
1129: return SSH_ERR_INVALID_ARGUMENT; /* overflow */
1.201 markus 1130: state->extra_pad = 0;
1.71 markus 1131: }
1.201 markus 1132: if ((r = sshbuf_reserve(state->outgoing_packet, padlen, &cp)) != 0)
1133: goto out;
1.235 djm 1134: if (enc && !cipher_ctx_is_plaintext(state->send_context)) {
1.32 markus 1135: /* random padding */
1.201 markus 1136: arc4random_buf(cp, padlen);
1.32 markus 1137: } else {
1138: /* clear padding */
1.192 djm 1139: explicit_bzero(cp, padlen);
1.25 markus 1140: }
1.178 markus 1141: /* sizeof (packet_len + pad_len + payload + padding) */
1.201 markus 1142: len = sshbuf_len(state->outgoing_packet);
1143: cp = sshbuf_mutable_ptr(state->outgoing_packet);
1144: if (cp == NULL) {
1145: r = SSH_ERR_INTERNAL_ERROR;
1146: goto out;
1147: }
1.25 markus 1148: /* packet_length includes payload, padding and padding length field */
1.201 markus 1149: POKE_U32(cp, len - 4);
1.89 markus 1150: cp[4] = padlen;
1.178 markus 1151: DBG(debug("send: len %d (includes padlen %d, aadlen %d)",
1152: len, padlen, aadlen));
1.25 markus 1153:
1154: /* compute MAC over seqnr and packet(length fields, payload, padding) */
1.178 markus 1155: if (mac && mac->enabled && !mac->etm) {
1.201 markus 1156: if ((r = mac_compute(mac, state->p_send.seqnr,
1157: sshbuf_ptr(state->outgoing_packet), len,
1.200 markus 1158: macbuf, sizeof(macbuf))) != 0)
1.201 markus 1159: goto out;
1160: DBG(debug("done calc MAC out #%d", state->p_send.seqnr));
1.25 markus 1161: }
1162: /* encrypt packet and append to output buffer. */
1.201 markus 1163: if ((r = sshbuf_reserve(state->output,
1164: sshbuf_len(state->outgoing_packet) + authlen, &cp)) != 0)
1165: goto out;
1.235 djm 1166: if ((r = cipher_crypt(state->send_context, state->p_send.seqnr, cp,
1.201 markus 1167: sshbuf_ptr(state->outgoing_packet),
1168: len - aadlen, aadlen, authlen)) != 0)
1169: goto out;
1.25 markus 1170: /* append unencrypted MAC */
1.178 markus 1171: if (mac && mac->enabled) {
1172: if (mac->etm) {
1173: /* EtM: compute mac over aadlen + cipher text */
1.201 markus 1174: if ((r = mac_compute(mac, state->p_send.seqnr,
1175: cp, len, macbuf, sizeof(macbuf))) != 0)
1176: goto out;
1.178 markus 1177: DBG(debug("done calc MAC(EtM) out #%d",
1.201 markus 1178: state->p_send.seqnr));
1.178 markus 1179: }
1.201 markus 1180: if ((r = sshbuf_put(state->output, macbuf, mac->mac_len)) != 0)
1181: goto out;
1.178 markus 1182: }
1.25 markus 1183: #ifdef PACKET_DEBUG
1184: fprintf(stderr, "encrypted: ");
1.201 markus 1185: sshbuf_dump(state->output, stderr);
1.25 markus 1186: #endif
1.29 markus 1187: /* increment sequence number for outgoing packets */
1.309.4.1! bluhm 1188: if (++state->p_send.seqnr == 0) {
! 1189: if ((ssh->kex->flags & KEX_INITIAL) != 0) {
! 1190: ssh_packet_disconnect(ssh, "outgoing sequence number "
! 1191: "wrapped during initial key exchange");
! 1192: }
1.106 itojun 1193: logit("outgoing seqnr wraps around");
1.309.4.1! bluhm 1194: }
1.201 markus 1195: if (++state->p_send.packets == 0)
1196: if (!(ssh->compat & SSH_BUG_NOREKEY))
1197: return SSH_ERR_NEED_REKEY;
1198: state->p_send.blocks += len / block_size;
1199: state->p_send.bytes += len;
1200: sshbuf_reset(state->outgoing_packet);
1.25 markus 1201:
1.309.4.1! bluhm 1202: if (type == SSH2_MSG_NEWKEYS && ssh->kex->kex_strict) {
! 1203: debug_f("resetting send seqnr %u", state->p_send.seqnr);
! 1204: state->p_send.seqnr = 0;
! 1205: }
! 1206:
1.57 markus 1207: if (type == SSH2_MSG_NEWKEYS)
1.201 markus 1208: r = ssh_set_newkeys(ssh, MODE_OUT);
1209: else if (type == SSH2_MSG_USERAUTH_SUCCESS && state->server_side)
1210: r = ssh_packet_enable_delayed_compress(ssh);
1211: else
1212: r = 0;
1213: out:
1214: return r;
1.25 markus 1215: }
1216:
1.228 djm 1217: /* returns non-zero if the specified packet type is usec by KEX */
1218: static int
1219: ssh_packet_type_is_kex(u_char type)
1220: {
1221: return
1222: type >= SSH2_MSG_TRANSPORT_MIN &&
1223: type <= SSH2_MSG_TRANSPORT_MAX &&
1224: type != SSH2_MSG_SERVICE_REQUEST &&
1225: type != SSH2_MSG_SERVICE_ACCEPT &&
1226: type != SSH2_MSG_EXT_INFO;
1227: }
1228:
1.201 markus 1229: int
1230: ssh_packet_send2(struct ssh *ssh)
1.105 markus 1231: {
1.201 markus 1232: struct session_state *state = ssh->state;
1.105 markus 1233: struct packet *p;
1.201 markus 1234: u_char type;
1.228 djm 1235: int r, need_rekey;
1.105 markus 1236:
1.228 djm 1237: if (sshbuf_len(state->outgoing_packet) < 6)
1238: return SSH_ERR_INTERNAL_ERROR;
1.201 markus 1239: type = sshbuf_ptr(state->outgoing_packet)[5];
1.228 djm 1240: need_rekey = !ssh_packet_type_is_kex(type) &&
1241: ssh_packet_need_rekeying(ssh, sshbuf_len(state->outgoing_packet));
1.105 markus 1242:
1.228 djm 1243: /*
1244: * During rekeying we can only send key exchange messages.
1245: * Queue everything else.
1246: */
1247: if ((need_rekey || state->rekeying) && !ssh_packet_type_is_kex(type)) {
1248: if (need_rekey)
1.297 djm 1249: debug3_f("rekex triggered");
1.228 djm 1250: debug("enqueue packet: %u", type);
1251: p = calloc(1, sizeof(*p));
1252: if (p == NULL)
1253: return SSH_ERR_ALLOC_FAIL;
1254: p->type = type;
1255: p->payload = state->outgoing_packet;
1256: TAILQ_INSERT_TAIL(&state->outgoing, p, next);
1257: state->outgoing_packet = sshbuf_new();
1258: if (state->outgoing_packet == NULL)
1259: return SSH_ERR_ALLOC_FAIL;
1260: if (need_rekey) {
1261: /*
1262: * This packet triggered a rekey, so send the
1263: * KEXINIT now.
1264: * NB. reenters this function via kex_start_rekex().
1265: */
1266: return kex_start_rekex(ssh);
1.105 markus 1267: }
1.228 djm 1268: return 0;
1.105 markus 1269: }
1270:
1271: /* rekeying starts with sending KEXINIT */
1272: if (type == SSH2_MSG_KEXINIT)
1.201 markus 1273: state->rekeying = 1;
1.105 markus 1274:
1.201 markus 1275: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1276: return r;
1.105 markus 1277:
1278: /* after a NEWKEYS message we can send the complete queue */
1279: if (type == SSH2_MSG_NEWKEYS) {
1.201 markus 1280: state->rekeying = 0;
1281: state->rekey_time = monotime();
1282: while ((p = TAILQ_FIRST(&state->outgoing))) {
1.105 markus 1283: type = p->type;
1.228 djm 1284: /*
1285: * If this packet triggers a rekex, then skip the
1286: * remaining packets in the queue for now.
1287: * NB. re-enters this function via kex_start_rekex.
1288: */
1289: if (ssh_packet_need_rekeying(ssh,
1290: sshbuf_len(p->payload))) {
1.297 djm 1291: debug3_f("queued packet triggered rekex");
1.228 djm 1292: return kex_start_rekex(ssh);
1293: }
1.105 markus 1294: debug("dequeue packet: %u", type);
1.201 markus 1295: sshbuf_free(state->outgoing_packet);
1296: state->outgoing_packet = p->payload;
1297: TAILQ_REMOVE(&state->outgoing, p, next);
1.228 djm 1298: memset(p, 0, sizeof(*p));
1.186 djm 1299: free(p);
1.201 markus 1300: if ((r = ssh_packet_send2_wrapped(ssh)) != 0)
1301: return r;
1.105 markus 1302: }
1303: }
1.201 markus 1304: return 0;
1.25 markus 1305: }
1306:
1307: /*
1.16 markus 1308: * Waits until a packet has been received, and returns its type. Note that
1309: * no other data is processed until this returns, so this function should not
1310: * be used during the interactive session.
1311: */
1.1 deraadt 1312:
1.2 provos 1313: int
1.201 markus 1314: ssh_packet_read_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.1 deraadt 1315: {
1.201 markus 1316: struct session_state *state = ssh->state;
1.309 dtucker 1317: int len, r, ms_remain = 0;
1.302 deraadt 1318: struct pollfd pfd;
1.14 markus 1319: char buf[8192];
1.302 deraadt 1320: struct timeval start;
1321: struct timespec timespec, *timespecp = NULL;
1.155 deraadt 1322:
1.25 markus 1323: DBG(debug("packet_read()"));
1.14 markus 1324:
1.205 djm 1325: /*
1326: * Since we are blocking, ensure that all written packets have
1327: * been sent.
1328: */
1.210 markus 1329: if ((r = ssh_packet_write_wait(ssh)) != 0)
1330: goto out;
1.14 markus 1331:
1332: /* Stay in the loop until we have received a complete packet. */
1333: for (;;) {
1334: /* Try to read a packet from the buffer. */
1.309.4.1! bluhm 1335: if ((r = ssh_packet_read_poll_seqnr(ssh, typep, seqnr_p)) != 0)
1.201 markus 1336: break;
1.14 markus 1337: /* If we got a packet, return it. */
1.201 markus 1338: if (*typep != SSH_MSG_NONE)
1339: break;
1.16 markus 1340: /*
1341: * Otherwise, wait for some data to arrive, add it to the
1342: * buffer, and try again.
1343: */
1.302 deraadt 1344: pfd.fd = state->connection_in;
1345: pfd.events = POLLIN;
1.16 markus 1346:
1.201 markus 1347: if (state->packet_timeout_ms > 0) {
1348: ms_remain = state->packet_timeout_ms;
1.302 deraadt 1349: timespecp = ×pec;
1.154 dtucker 1350: }
1.14 markus 1351: /* Wait for some data to arrive. */
1.154 dtucker 1352: for (;;) {
1.291 markus 1353: if (state->packet_timeout_ms > 0) {
1.302 deraadt 1354: ms_to_timespec(×pec, ms_remain);
1.267 dtucker 1355: monotime_tv(&start);
1.154 dtucker 1356: }
1.302 deraadt 1357: if ((r = ppoll(&pfd, 1, timespecp, NULL)) >= 0)
1.154 dtucker 1358: break;
1.270 dtucker 1359: if (errno != EAGAIN && errno != EINTR) {
1360: r = SSH_ERR_SYSTEM_ERROR;
1361: goto out;
1362: }
1.291 markus 1363: if (state->packet_timeout_ms <= 0)
1.154 dtucker 1364: continue;
1365: ms_subtract_diff(&start, &ms_remain);
1366: if (ms_remain <= 0) {
1.201 markus 1367: r = 0;
1.154 dtucker 1368: break;
1369: }
1370: }
1.246 djm 1371: if (r == 0) {
1372: r = SSH_ERR_CONN_TIMEOUT;
1373: goto out;
1374: }
1.14 markus 1375: /* Read data from the socket. */
1.222 markus 1376: len = read(state->connection_in, buf, sizeof(buf));
1.210 markus 1377: if (len == 0) {
1378: r = SSH_ERR_CONN_CLOSED;
1379: goto out;
1380: }
1.286 deraadt 1381: if (len == -1) {
1.210 markus 1382: r = SSH_ERR_SYSTEM_ERROR;
1383: goto out;
1384: }
1.204 djm 1385:
1.14 markus 1386: /* Append it to the buffer. */
1.204 djm 1387: if ((r = ssh_packet_process_incoming(ssh, buf, len)) != 0)
1.210 markus 1388: goto out;
1.14 markus 1389: }
1.210 markus 1390: out:
1.201 markus 1391: return r;
1.1 deraadt 1392: }
1393:
1.77 djm 1394: int
1.201 markus 1395: ssh_packet_read(struct ssh *ssh)
1.77 djm 1396: {
1.201 markus 1397: u_char type;
1398: int r;
1399:
1400: if ((r = ssh_packet_read_seqnr(ssh, &type, NULL)) != 0)
1.297 djm 1401: fatal_fr(r, "read");
1.201 markus 1402: return type;
1.77 djm 1403: }
1404:
1.242 markus 1405: static int
1406: ssh_packet_read_poll2_mux(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1407: {
1408: struct session_state *state = ssh->state;
1409: const u_char *cp;
1410: size_t need;
1411: int r;
1412:
1413: if (ssh->kex)
1414: return SSH_ERR_INTERNAL_ERROR;
1415: *typep = SSH_MSG_NONE;
1416: cp = sshbuf_ptr(state->input);
1417: if (state->packlen == 0) {
1418: if (sshbuf_len(state->input) < 4 + 1)
1419: return 0; /* packet is incomplete */
1420: state->packlen = PEEK_U32(cp);
1421: if (state->packlen < 4 + 1 ||
1422: state->packlen > PACKET_MAX_SIZE)
1423: return SSH_ERR_MESSAGE_INCOMPLETE;
1424: }
1425: need = state->packlen + 4;
1426: if (sshbuf_len(state->input) < need)
1427: return 0; /* packet is incomplete */
1428: sshbuf_reset(state->incoming_packet);
1429: if ((r = sshbuf_put(state->incoming_packet, cp + 4,
1430: state->packlen)) != 0 ||
1431: (r = sshbuf_consume(state->input, need)) != 0 ||
1432: (r = sshbuf_get_u8(state->incoming_packet, NULL)) != 0 ||
1433: (r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1434: return r;
1435: if (ssh_packet_log_type(*typep))
1.297 djm 1436: debug3_f("type %u", *typep);
1.242 markus 1437: /* sshbuf_dump(state->incoming_packet, stderr); */
1438: /* reset for next packet */
1439: state->packlen = 0;
1440: return r;
1441: }
1442:
1.201 markus 1443: int
1444: ssh_packet_read_poll2(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1445: {
1.201 markus 1446: struct session_state *state = ssh->state;
1.40 markus 1447: u_int padlen, need;
1.231 djm 1448: u_char *cp;
1.201 markus 1449: u_int maclen, aadlen = 0, authlen = 0, block_size;
1450: struct sshenc *enc = NULL;
1451: struct sshmac *mac = NULL;
1452: struct sshcomp *comp = NULL;
1.200 markus 1453: int r;
1.201 markus 1454:
1.242 markus 1455: if (state->mux)
1456: return ssh_packet_read_poll2_mux(ssh, typep, seqnr_p);
1457:
1.201 markus 1458: *typep = SSH_MSG_NONE;
1459:
1460: if (state->packet_discard)
1461: return 0;
1462:
1463: if (state->newkeys[MODE_IN] != NULL) {
1464: enc = &state->newkeys[MODE_IN]->enc;
1465: mac = &state->newkeys[MODE_IN]->mac;
1466: comp = &state->newkeys[MODE_IN]->comp;
1.180 markus 1467: /* disable mac for authenticated encryption */
1468: if ((authlen = cipher_authlen(enc->cipher)) != 0)
1469: mac = NULL;
1.25 markus 1470: }
1471: maclen = mac && mac->enabled ? mac->mac_len : 0;
1.88 markus 1472: block_size = enc ? enc->block_size : 8;
1.180 markus 1473: aadlen = (mac && mac->enabled && mac->etm) || authlen ? 4 : 0;
1.25 markus 1474:
1.201 markus 1475: if (aadlen && state->packlen == 0) {
1.235 djm 1476: if (cipher_get_length(state->receive_context,
1.201 markus 1477: &state->packlen, state->p_read.seqnr,
1478: sshbuf_ptr(state->input), sshbuf_len(state->input)) != 0)
1479: return 0;
1480: if (state->packlen < 1 + 4 ||
1481: state->packlen > PACKET_MAX_SIZE) {
1.178 markus 1482: #ifdef PACKET_DEBUG
1.201 markus 1483: sshbuf_dump(state->input, stderr);
1.178 markus 1484: #endif
1.201 markus 1485: logit("Bad packet length %u.", state->packlen);
1486: if ((r = sshpkt_disconnect(ssh, "Packet corrupt")) != 0)
1487: return r;
1.217 djm 1488: return SSH_ERR_CONN_CORRUPT;
1.178 markus 1489: }
1.201 markus 1490: sshbuf_reset(state->incoming_packet);
1491: } else if (state->packlen == 0) {
1.25 markus 1492: /*
1493: * check if input size is less than the cipher block size,
1494: * decrypt first block and extract length of incoming packet
1495: */
1.201 markus 1496: if (sshbuf_len(state->input) < block_size)
1497: return 0;
1498: sshbuf_reset(state->incoming_packet);
1499: if ((r = sshbuf_reserve(state->incoming_packet, block_size,
1500: &cp)) != 0)
1501: goto out;
1.235 djm 1502: if ((r = cipher_crypt(state->receive_context,
1.201 markus 1503: state->p_send.seqnr, cp, sshbuf_ptr(state->input),
1504: block_size, 0, 0)) != 0)
1505: goto out;
1506: state->packlen = PEEK_U32(sshbuf_ptr(state->incoming_packet));
1507: if (state->packlen < 1 + 4 ||
1508: state->packlen > PACKET_MAX_SIZE) {
1.110 markus 1509: #ifdef PACKET_DEBUG
1.201 markus 1510: fprintf(stderr, "input: \n");
1511: sshbuf_dump(state->input, stderr);
1512: fprintf(stderr, "incoming_packet: \n");
1513: sshbuf_dump(state->incoming_packet, stderr);
1.110 markus 1514: #endif
1.201 markus 1515: logit("Bad packet length %u.", state->packlen);
1.234 markus 1516: return ssh_packet_start_discard(ssh, enc, mac, 0,
1517: PACKET_MAX_SIZE);
1.25 markus 1518: }
1.201 markus 1519: if ((r = sshbuf_consume(state->input, block_size)) != 0)
1520: goto out;
1.25 markus 1521: }
1.201 markus 1522: DBG(debug("input: packet len %u", state->packlen+4));
1523:
1.178 markus 1524: if (aadlen) {
1525: /* only the payload is encrypted */
1.201 markus 1526: need = state->packlen;
1.178 markus 1527: } else {
1528: /*
1529: * the payload size and the payload are encrypted, but we
1530: * have a partial packet of block_size bytes
1531: */
1.201 markus 1532: need = 4 + state->packlen - block_size;
1.178 markus 1533: }
1.180 markus 1534: DBG(debug("partial packet: block %d, need %d, maclen %d, authlen %d,"
1535: " aadlen %d", block_size, need, maclen, authlen, aadlen));
1.158 markus 1536: if (need % block_size != 0) {
1537: logit("padding error: need %d block %d mod %d",
1.25 markus 1538: need, block_size, need % block_size);
1.234 markus 1539: return ssh_packet_start_discard(ssh, enc, mac, 0,
1540: PACKET_MAX_SIZE - block_size);
1.158 markus 1541: }
1.25 markus 1542: /*
1543: * check if the entire packet has been received and
1.178 markus 1544: * decrypt into incoming_packet:
1545: * 'aadlen' bytes are unencrypted, but authenticated.
1.180 markus 1546: * 'need' bytes are encrypted, followed by either
1547: * 'authlen' bytes of authentication tag or
1.178 markus 1548: * 'maclen' bytes of message authentication code.
1.25 markus 1549: */
1.201 markus 1550: if (sshbuf_len(state->input) < aadlen + need + authlen + maclen)
1.231 djm 1551: return 0; /* packet is incomplete */
1.25 markus 1552: #ifdef PACKET_DEBUG
1553: fprintf(stderr, "read_poll enc/full: ");
1.201 markus 1554: sshbuf_dump(state->input, stderr);
1.25 markus 1555: #endif
1.231 djm 1556: /* EtM: check mac over encrypted input */
1.201 markus 1557: if (mac && mac->enabled && mac->etm) {
1.231 djm 1558: if ((r = mac_check(mac, state->p_read.seqnr,
1.201 markus 1559: sshbuf_ptr(state->input), aadlen + need,
1.231 djm 1560: sshbuf_ptr(state->input) + aadlen + need + authlen,
1561: maclen)) != 0) {
1562: if (r == SSH_ERR_MAC_INVALID)
1563: logit("Corrupted MAC on input.");
1.201 markus 1564: goto out;
1.231 djm 1565: }
1.201 markus 1566: }
1567: if ((r = sshbuf_reserve(state->incoming_packet, aadlen + need,
1568: &cp)) != 0)
1569: goto out;
1.235 djm 1570: if ((r = cipher_crypt(state->receive_context, state->p_read.seqnr, cp,
1.201 markus 1571: sshbuf_ptr(state->input), need, aadlen, authlen)) != 0)
1572: goto out;
1573: if ((r = sshbuf_consume(state->input, aadlen + need + authlen)) != 0)
1574: goto out;
1.29 markus 1575: if (mac && mac->enabled) {
1.231 djm 1576: /* Not EtM: check MAC over cleartext */
1577: if (!mac->etm && (r = mac_check(mac, state->p_read.seqnr,
1578: sshbuf_ptr(state->incoming_packet),
1579: sshbuf_len(state->incoming_packet),
1580: sshbuf_ptr(state->input), maclen)) != 0) {
1581: if (r != SSH_ERR_MAC_INVALID)
1.201 markus 1582: goto out;
1.159 markus 1583: logit("Corrupted MAC on input.");
1.247 markus 1584: if (need + block_size > PACKET_MAX_SIZE)
1.201 markus 1585: return SSH_ERR_INTERNAL_ERROR;
1586: return ssh_packet_start_discard(ssh, enc, mac,
1.234 markus 1587: sshbuf_len(state->incoming_packet),
1.247 markus 1588: PACKET_MAX_SIZE - need - block_size);
1.201 markus 1589: }
1.231 djm 1590: /* Remove MAC from input buffer */
1.201 markus 1591: DBG(debug("MAC #%d ok", state->p_read.seqnr));
1592: if ((r = sshbuf_consume(state->input, mac->mac_len)) != 0)
1593: goto out;
1.25 markus 1594: }
1.309.4.1! bluhm 1595:
1.77 djm 1596: if (seqnr_p != NULL)
1.201 markus 1597: *seqnr_p = state->p_read.seqnr;
1.309.4.1! bluhm 1598: if (++state->p_read.seqnr == 0) {
! 1599: if ((ssh->kex->flags & KEX_INITIAL) != 0) {
! 1600: ssh_packet_disconnect(ssh, "incoming sequence number "
! 1601: "wrapped during initial key exchange");
! 1602: }
1.106 itojun 1603: logit("incoming seqnr wraps around");
1.309.4.1! bluhm 1604: }
1.201 markus 1605: if (++state->p_read.packets == 0)
1606: if (!(ssh->compat & SSH_BUG_NOREKEY))
1607: return SSH_ERR_NEED_REKEY;
1608: state->p_read.blocks += (state->packlen + 4) / block_size;
1609: state->p_read.bytes += state->packlen + 4;
1.25 markus 1610:
1611: /* get padlen */
1.201 markus 1612: padlen = sshbuf_ptr(state->incoming_packet)[4];
1.25 markus 1613: DBG(debug("input: padlen %d", padlen));
1.205 djm 1614: if (padlen < 4) {
1615: if ((r = sshpkt_disconnect(ssh,
1616: "Corrupted padlen %d on input.", padlen)) != 0 ||
1617: (r = ssh_packet_write_wait(ssh)) != 0)
1618: return r;
1619: return SSH_ERR_CONN_CORRUPT;
1620: }
1.25 markus 1621:
1622: /* skip packet size + padlen, discard padding */
1.201 markus 1623: if ((r = sshbuf_consume(state->incoming_packet, 4 + 1)) != 0 ||
1624: ((r = sshbuf_consume_end(state->incoming_packet, padlen)) != 0))
1625: goto out;
1.25 markus 1626:
1.201 markus 1627: DBG(debug("input: len before de-compress %zd",
1628: sshbuf_len(state->incoming_packet)));
1.25 markus 1629: if (comp && comp->enabled) {
1.201 markus 1630: sshbuf_reset(state->compression_buffer);
1631: if ((r = uncompress_buffer(ssh, state->incoming_packet,
1632: state->compression_buffer)) != 0)
1633: goto out;
1634: sshbuf_reset(state->incoming_packet);
1635: if ((r = sshbuf_putb(state->incoming_packet,
1636: state->compression_buffer)) != 0)
1637: goto out;
1638: DBG(debug("input: len after de-compress %zd",
1639: sshbuf_len(state->incoming_packet)));
1.25 markus 1640: }
1641: /*
1642: * get packet type, implies consume.
1643: * return length of payload (without type field)
1644: */
1.201 markus 1645: if ((r = sshbuf_get_u8(state->incoming_packet, typep)) != 0)
1646: goto out;
1.226 djm 1647: if (ssh_packet_log_type(*typep))
1648: debug3("receive packet: type %u", *typep);
1.205 djm 1649: if (*typep < SSH2_MSG_MIN || *typep >= SSH2_MSG_LOCAL_MIN) {
1650: if ((r = sshpkt_disconnect(ssh,
1651: "Invalid ssh2 packet type: %d", *typep)) != 0 ||
1652: (r = ssh_packet_write_wait(ssh)) != 0)
1653: return r;
1654: return SSH_ERR_PROTOCOL_ERROR;
1655: }
1.243 djm 1656: if (state->hook_in != NULL &&
1657: (r = state->hook_in(ssh, state->incoming_packet, typep,
1658: state->hook_in_ctx)) != 0)
1659: return r;
1.238 markus 1660: if (*typep == SSH2_MSG_USERAUTH_SUCCESS && !state->server_side)
1.201 markus 1661: r = ssh_packet_enable_delayed_compress(ssh);
1662: else
1663: r = 0;
1.25 markus 1664: #ifdef PACKET_DEBUG
1.201 markus 1665: fprintf(stderr, "read/plain[%d]:\r\n", *typep);
1666: sshbuf_dump(state->incoming_packet, stderr);
1.25 markus 1667: #endif
1.62 markus 1668: /* reset for next packet */
1.201 markus 1669: state->packlen = 0;
1.309.4.1! bluhm 1670: if (*typep == SSH2_MSG_NEWKEYS && ssh->kex->kex_strict) {
! 1671: debug_f("resetting read seqnr %u", state->p_read.seqnr);
! 1672: state->p_read.seqnr = 0;
! 1673: }
1.228 djm 1674:
1.301 djm 1675: if ((r = ssh_packet_check_rekey(ssh)) != 0)
1676: return r;
1.201 markus 1677: out:
1678: return r;
1.25 markus 1679: }
1680:
1681: int
1.201 markus 1682: ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p)
1.25 markus 1683: {
1.201 markus 1684: struct session_state *state = ssh->state;
1.96 deraadt 1685: u_int reason, seqnr;
1.201 markus 1686: int r;
1687: u_char *msg;
1.62 markus 1688:
1.25 markus 1689: for (;;) {
1.201 markus 1690: msg = NULL;
1.249 djm 1691: r = ssh_packet_read_poll2(ssh, typep, seqnr_p);
1692: if (r != 0)
1693: return r;
1.309.4.1! bluhm 1694: if (*typep == 0) {
! 1695: /* no message ready */
! 1696: return 0;
1.249 djm 1697: }
1.309.4.1! bluhm 1698: state->keep_alive_timeouts = 0;
! 1699: DBG(debug("received packet type %d", *typep));
! 1700:
! 1701: /* Always process disconnect messages */
! 1702: if (*typep == SSH2_MSG_DISCONNECT) {
! 1703: if ((r = sshpkt_get_u32(ssh, &reason)) != 0 ||
! 1704: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0)
! 1705: return r;
! 1706: /* Ignore normal client exit notifications */
! 1707: do_log2(ssh->state->server_side &&
! 1708: reason == SSH2_DISCONNECT_BY_APPLICATION ?
! 1709: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_ERROR,
! 1710: "Received disconnect from %s port %d:"
! 1711: "%u: %.400s", ssh_remote_ipaddr(ssh),
! 1712: ssh_remote_port(ssh), reason, msg);
! 1713: free(msg);
! 1714: return SSH_ERR_DISCONNECTED;
! 1715: }
! 1716:
! 1717: /*
! 1718: * Do not implicitly handle any messages here during initial
! 1719: * KEX when in strict mode. They will be need to be allowed
! 1720: * explicitly by the KEX dispatch table or they will generate
! 1721: * protocol errors.
! 1722: */
! 1723: if (ssh->kex != NULL &&
! 1724: (ssh->kex->flags & KEX_INITIAL) && ssh->kex->kex_strict)
! 1725: return 0;
! 1726: /* Implicitly handle transport-level messages */
1.249 djm 1727: switch (*typep) {
1728: case SSH2_MSG_IGNORE:
1729: debug3("Received SSH2_MSG_IGNORE");
1730: break;
1731: case SSH2_MSG_DEBUG:
1732: if ((r = sshpkt_get_u8(ssh, NULL)) != 0 ||
1733: (r = sshpkt_get_string(ssh, &msg, NULL)) != 0 ||
1734: (r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
1735: free(msg);
1.201 markus 1736: return r;
1.48 stevesk 1737: }
1.249 djm 1738: debug("Remote: %.900s", msg);
1739: free(msg);
1740: break;
1741: case SSH2_MSG_UNIMPLEMENTED:
1742: if ((r = sshpkt_get_u32(ssh, &seqnr)) != 0)
1743: return r;
1744: debug("Received SSH2_MSG_UNIMPLEMENTED for %u",
1745: seqnr);
1746: break;
1747: default:
1748: return 0;
1.25 markus 1749: }
1750: }
1751: }
1752:
1.16 markus 1753: /*
1.306 djm 1754: * Buffers the supplied input data. This is intended to be used together
1755: * with packet_read_poll().
1.16 markus 1756: */
1.204 djm 1757: int
1.201 markus 1758: ssh_packet_process_incoming(struct ssh *ssh, const char *buf, u_int len)
1.1 deraadt 1759: {
1.201 markus 1760: struct session_state *state = ssh->state;
1761: int r;
1762:
1763: if (state->packet_discard) {
1764: state->keep_alive_timeouts = 0; /* ?? */
1765: if (len >= state->packet_discard) {
1766: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1.204 djm 1767: return r;
1.201 markus 1768: }
1769: state->packet_discard -= len;
1.204 djm 1770: return 0;
1.159 markus 1771: }
1.306 djm 1772: if ((r = sshbuf_put(state->input, buf, len)) != 0)
1.204 djm 1773: return r;
1774:
1.307 djm 1775: return 0;
1776: }
1777:
1778: /* Reads and buffers data from the specified fd */
1779: int
1780: ssh_packet_process_read(struct ssh *ssh, int fd)
1781: {
1782: struct session_state *state = ssh->state;
1783: int r;
1784: size_t rlen;
1785:
1786: if ((r = sshbuf_read(fd, state->input, PACKET_MAX_SIZE, &rlen)) != 0)
1787: return r;
1788:
1789: if (state->packet_discard) {
1790: if ((r = sshbuf_consume_end(state->input, rlen)) != 0)
1791: return r;
1792: state->keep_alive_timeouts = 0; /* ?? */
1793: if (rlen >= state->packet_discard) {
1794: if ((r = ssh_packet_stop_discard(ssh)) != 0)
1795: return r;
1796: }
1797: state->packet_discard -= rlen;
1798: return 0;
1799: }
1.204 djm 1800: return 0;
1.28 markus 1801: }
1802:
1803: int
1.201 markus 1804: ssh_packet_remaining(struct ssh *ssh)
1.28 markus 1805: {
1.201 markus 1806: return sshbuf_len(ssh->state->incoming_packet);
1.1 deraadt 1807: }
1808:
1.16 markus 1809: /*
1810: * Sends a diagnostic message from the server to the client. This message
1811: * can be sent at any time (but not while constructing another message). The
1812: * message is printed immediately, but only if the client is being executed
1813: * in verbose mode. These messages are primarily intended to ease debugging
1814: * authentication problems. The length of the formatted message must not
1.205 djm 1815: * exceed 1024 bytes. This will automatically call ssh_packet_write_wait.
1.16 markus 1816: */
1.2 provos 1817: void
1.201 markus 1818: ssh_packet_send_debug(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1819: {
1.14 markus 1820: char buf[1024];
1821: va_list args;
1.201 markus 1822: int r;
1.39 markus 1823:
1.249 djm 1824: if ((ssh->compat & SSH_BUG_DEBUG))
1.39 markus 1825: return;
1.14 markus 1826:
1827: va_start(args, fmt);
1828: vsnprintf(buf, sizeof(buf), fmt, args);
1829: va_end(args);
1.265 djm 1830:
1831: debug3("sending debug message: %s", buf);
1.14 markus 1832:
1.249 djm 1833: if ((r = sshpkt_start(ssh, SSH2_MSG_DEBUG)) != 0 ||
1834: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* always display */
1835: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
1836: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1837: (r = sshpkt_send(ssh)) != 0 ||
1838: (r = ssh_packet_write_wait(ssh)) != 0)
1.297 djm 1839: fatal_fr(r, "send DEBUG");
1.205 djm 1840: }
1841:
1.268 dtucker 1842: void
1843: sshpkt_fmt_connection_id(struct ssh *ssh, char *s, size_t l)
1.245 djm 1844: {
1845: snprintf(s, l, "%.200s%s%s port %d",
1846: ssh->log_preamble ? ssh->log_preamble : "",
1847: ssh->log_preamble ? " " : "",
1848: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1849: }
1850:
1.205 djm 1851: /*
1852: * Pretty-print connection-terminating errors and exit.
1853: */
1.280 djm 1854: static void
1855: sshpkt_vfatal(struct ssh *ssh, int r, const char *fmt, va_list ap)
1.205 djm 1856: {
1.280 djm 1857: char *tag = NULL, remote_id[512];
1.290 djm 1858: int oerrno = errno;
1.245 djm 1859:
1.268 dtucker 1860: sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1.245 djm 1861:
1.205 djm 1862: switch (r) {
1863: case SSH_ERR_CONN_CLOSED:
1.257 markus 1864: ssh_packet_clear_keys(ssh);
1.245 djm 1865: logdie("Connection closed by %s", remote_id);
1.205 djm 1866: case SSH_ERR_CONN_TIMEOUT:
1.257 markus 1867: ssh_packet_clear_keys(ssh);
1.245 djm 1868: logdie("Connection %s %s timed out",
1869: ssh->state->server_side ? "from" : "to", remote_id);
1.212 djm 1870: case SSH_ERR_DISCONNECTED:
1.257 markus 1871: ssh_packet_clear_keys(ssh);
1.245 djm 1872: logdie("Disconnected from %s", remote_id);
1.212 djm 1873: case SSH_ERR_SYSTEM_ERROR:
1.257 markus 1874: if (errno == ECONNRESET) {
1875: ssh_packet_clear_keys(ssh);
1.245 djm 1876: logdie("Connection reset by %s", remote_id);
1.257 markus 1877: }
1.213 djm 1878: /* FALLTHROUGH */
1879: case SSH_ERR_NO_CIPHER_ALG_MATCH:
1880: case SSH_ERR_NO_MAC_ALG_MATCH:
1881: case SSH_ERR_NO_COMPRESS_ALG_MATCH:
1882: case SSH_ERR_NO_KEX_ALG_MATCH:
1883: case SSH_ERR_NO_HOSTKEY_ALG_MATCH:
1884: if (ssh && ssh->kex && ssh->kex->failed_choice) {
1.257 markus 1885: ssh_packet_clear_keys(ssh);
1.290 djm 1886: errno = oerrno;
1.245 djm 1887: logdie("Unable to negotiate with %s: %s. "
1888: "Their offer: %s", remote_id, ssh_err(r),
1.220 djm 1889: ssh->kex->failed_choice);
1.212 djm 1890: }
1891: /* FALLTHROUGH */
1.205 djm 1892: default:
1.280 djm 1893: if (vasprintf(&tag, fmt, ap) == -1) {
1894: ssh_packet_clear_keys(ssh);
1.297 djm 1895: logdie_f("could not allocate failure message");
1.280 djm 1896: }
1.257 markus 1897: ssh_packet_clear_keys(ssh);
1.290 djm 1898: errno = oerrno;
1.297 djm 1899: logdie_r(r, "%s%sConnection %s %s",
1.205 djm 1900: tag != NULL ? tag : "", tag != NULL ? ": " : "",
1.297 djm 1901: ssh->state->server_side ? "from" : "to", remote_id);
1.205 djm 1902: }
1.1 deraadt 1903: }
1904:
1.280 djm 1905: void
1906: sshpkt_fatal(struct ssh *ssh, int r, const char *fmt, ...)
1907: {
1908: va_list ap;
1909:
1910: va_start(ap, fmt);
1911: sshpkt_vfatal(ssh, r, fmt, ap);
1912: /* NOTREACHED */
1913: va_end(ap);
1.297 djm 1914: logdie_f("should have exited");
1.280 djm 1915: }
1916:
1.16 markus 1917: /*
1918: * Logs the error plus constructs and sends a disconnect packet, closes the
1919: * connection, and exits. This function never returns. The error message
1920: * should not contain a newline. The length of the formatted message must
1921: * not exceed 1024 bytes.
1922: */
1.2 provos 1923: void
1.201 markus 1924: ssh_packet_disconnect(struct ssh *ssh, const char *fmt,...)
1.1 deraadt 1925: {
1.245 djm 1926: char buf[1024], remote_id[512];
1.14 markus 1927: va_list args;
1928: static int disconnecting = 0;
1.201 markus 1929: int r;
1.97 deraadt 1930:
1.14 markus 1931: if (disconnecting) /* Guard against recursive invocations. */
1932: fatal("packet_disconnect called recursively.");
1933: disconnecting = 1;
1934:
1.16 markus 1935: /*
1936: * Format the message. Note that the caller must make sure the
1937: * message is of limited size.
1938: */
1.268 dtucker 1939: sshpkt_fmt_connection_id(ssh, remote_id, sizeof(remote_id));
1.14 markus 1940: va_start(args, fmt);
1941: vsnprintf(buf, sizeof(buf), fmt, args);
1942: va_end(args);
1943:
1.99 markus 1944: /* Display the error locally */
1.245 djm 1945: logit("Disconnecting %s: %.100s", remote_id, buf);
1.99 markus 1946:
1.205 djm 1947: /*
1948: * Send the disconnect message to the other side, and wait
1949: * for it to get sent.
1950: */
1951: if ((r = sshpkt_disconnect(ssh, "%s", buf)) != 0)
1.280 djm 1952: sshpkt_fatal(ssh, r, "%s", __func__);
1.205 djm 1953:
1954: if ((r = ssh_packet_write_wait(ssh)) != 0)
1.280 djm 1955: sshpkt_fatal(ssh, r, "%s", __func__);
1.14 markus 1956:
1957: /* Close the connection. */
1.201 markus 1958: ssh_packet_close(ssh);
1.112 markus 1959: cleanup_exit(255);
1.1 deraadt 1960: }
1961:
1.205 djm 1962: /*
1963: * Checks if there is any buffered output, and tries to write some of
1964: * the output.
1965: */
1966: int
1.201 markus 1967: ssh_packet_write_poll(struct ssh *ssh)
1.1 deraadt 1968: {
1.201 markus 1969: struct session_state *state = ssh->state;
1970: int len = sshbuf_len(state->output);
1.222 markus 1971: int r;
1.97 deraadt 1972:
1.14 markus 1973: if (len > 0) {
1.222 markus 1974: len = write(state->connection_out,
1975: sshbuf_ptr(state->output), len);
1.156 djm 1976: if (len == -1) {
1977: if (errno == EINTR || errno == EAGAIN)
1.205 djm 1978: return 0;
1979: return SSH_ERR_SYSTEM_ERROR;
1.14 markus 1980: }
1.222 markus 1981: if (len == 0)
1.205 djm 1982: return SSH_ERR_CONN_CLOSED;
1.201 markus 1983: if ((r = sshbuf_consume(state->output, len)) != 0)
1.205 djm 1984: return r;
1.14 markus 1985: }
1.205 djm 1986: return 0;
1.1 deraadt 1987: }
1988:
1.16 markus 1989: /*
1990: * Calls packet_write_poll repeatedly until all pending output data has been
1991: * written.
1992: */
1.205 djm 1993: int
1.201 markus 1994: ssh_packet_write_wait(struct ssh *ssh)
1.1 deraadt 1995: {
1.205 djm 1996: int ret, r, ms_remain = 0;
1.302 deraadt 1997: struct timeval start;
1998: struct timespec timespec, *timespecp = NULL;
1.201 markus 1999: struct session_state *state = ssh->state;
1.302 deraadt 2000: struct pollfd pfd;
1.56 millert 2001:
1.302 deraadt 2002: if ((r = ssh_packet_write_poll(ssh)) != 0)
1.215 djm 2003: return r;
1.201 markus 2004: while (ssh_packet_have_data_to_write(ssh)) {
1.302 deraadt 2005: pfd.fd = state->connection_out;
2006: pfd.events = POLLOUT;
1.154 dtucker 2007:
1.201 markus 2008: if (state->packet_timeout_ms > 0) {
2009: ms_remain = state->packet_timeout_ms;
1.302 deraadt 2010: timespecp = ×pec;
1.154 dtucker 2011: }
2012: for (;;) {
1.291 markus 2013: if (state->packet_timeout_ms > 0) {
1.302 deraadt 2014: ms_to_timespec(×pec, ms_remain);
1.267 dtucker 2015: monotime_tv(&start);
1.154 dtucker 2016: }
1.302 deraadt 2017: if ((ret = ppoll(&pfd, 1, timespecp, NULL)) >= 0)
1.154 dtucker 2018: break;
1.161 andreas 2019: if (errno != EAGAIN && errno != EINTR)
1.154 dtucker 2020: break;
1.291 markus 2021: if (state->packet_timeout_ms <= 0)
1.154 dtucker 2022: continue;
2023: ms_subtract_diff(&start, &ms_remain);
2024: if (ms_remain <= 0) {
2025: ret = 0;
2026: break;
2027: }
2028: }
1.302 deraadt 2029: if (ret == 0)
1.205 djm 2030: return SSH_ERR_CONN_TIMEOUT;
1.302 deraadt 2031: if ((r = ssh_packet_write_poll(ssh)) != 0)
1.205 djm 2032: return r;
1.14 markus 2033: }
1.205 djm 2034: return 0;
1.1 deraadt 2035: }
2036:
2037: /* Returns true if there is buffered data to write to the connection. */
2038:
1.2 provos 2039: int
1.201 markus 2040: ssh_packet_have_data_to_write(struct ssh *ssh)
1.1 deraadt 2041: {
1.201 markus 2042: return sshbuf_len(ssh->state->output) != 0;
1.1 deraadt 2043: }
2044:
2045: /* Returns true if there is not too much data to write to the connection. */
2046:
1.2 provos 2047: int
1.201 markus 2048: ssh_packet_not_very_much_data_to_write(struct ssh *ssh)
1.1 deraadt 2049: {
1.201 markus 2050: if (ssh->state->interactive_mode)
2051: return sshbuf_len(ssh->state->output) < 16384;
1.14 markus 2052: else
1.201 markus 2053: return sshbuf_len(ssh->state->output) < 128 * 1024;
1.1 deraadt 2054: }
2055:
1.201 markus 2056: void
2057: ssh_packet_set_tos(struct ssh *ssh, int tos)
1.101 markus 2058: {
1.263 djm 2059: if (!ssh_packet_connection_is_on_socket(ssh) || tos == INT_MAX)
1.101 markus 2060: return;
1.298 djm 2061: set_sock_tos(ssh->state->connection_in, tos);
1.101 markus 2062: }
2063:
1.1 deraadt 2064: /* Informs that the current session is interactive. Sets IP flags for that. */
2065:
1.2 provos 2066: void
1.201 markus 2067: ssh_packet_set_interactive(struct ssh *ssh, int interactive, int qos_interactive, int qos_bulk)
1.1 deraadt 2068: {
1.201 markus 2069: struct session_state *state = ssh->state;
2070:
2071: if (state->set_interactive_called)
1.43 markus 2072: return;
1.201 markus 2073: state->set_interactive_called = 1;
1.1 deraadt 2074:
1.14 markus 2075: /* Record that we are in interactive mode. */
1.201 markus 2076: state->interactive_mode = interactive;
1.1 deraadt 2077:
1.19 markus 2078: /* Only set socket options if using a socket. */
1.201 markus 2079: if (!ssh_packet_connection_is_on_socket(ssh))
1.14 markus 2080: return;
1.201 markus 2081: set_nodelay(state->connection_in);
1.298 djm 2082: ssh_packet_set_tos(ssh, interactive ? qos_interactive : qos_bulk);
1.1 deraadt 2083: }
2084:
2085: /* Returns true if the current connection is interactive. */
2086:
1.2 provos 2087: int
1.201 markus 2088: ssh_packet_is_interactive(struct ssh *ssh)
1.1 deraadt 2089: {
1.201 markus 2090: return ssh->state->interactive_mode;
1.12 markus 2091: }
2092:
1.113 deraadt 2093: int
1.201 markus 2094: ssh_packet_set_maxsize(struct ssh *ssh, u_int s)
1.12 markus 2095: {
1.201 markus 2096: struct session_state *state = ssh->state;
2097:
2098: if (state->set_maxsize_called) {
1.303 djm 2099: logit_f("called twice: old %d new %d",
1.201 markus 2100: state->max_packet_size, s);
1.14 markus 2101: return -1;
2102: }
2103: if (s < 4 * 1024 || s > 1024 * 1024) {
1.303 djm 2104: logit_f("bad size %d", s);
1.14 markus 2105: return -1;
2106: }
1.201 markus 2107: state->set_maxsize_called = 1;
1.303 djm 2108: debug_f("setting to %d", s);
1.201 markus 2109: state->max_packet_size = s;
1.14 markus 2110: return s;
1.53 markus 2111: }
2112:
1.161 andreas 2113: int
1.201 markus 2114: ssh_packet_inc_alive_timeouts(struct ssh *ssh)
1.161 andreas 2115: {
1.201 markus 2116: return ++ssh->state->keep_alive_timeouts;
1.161 andreas 2117: }
2118:
2119: void
1.201 markus 2120: ssh_packet_set_alive_timeouts(struct ssh *ssh, int ka)
1.161 andreas 2121: {
1.201 markus 2122: ssh->state->keep_alive_timeouts = ka;
1.161 andreas 2123: }
2124:
2125: u_int
1.201 markus 2126: ssh_packet_get_maxsize(struct ssh *ssh)
1.71 markus 2127: {
1.201 markus 2128: return ssh->state->max_packet_size;
1.71 markus 2129: }
2130:
1.105 markus 2131: void
1.244 dtucker 2132: ssh_packet_set_rekey_limits(struct ssh *ssh, u_int64_t bytes, u_int32_t seconds)
1.105 markus 2133: {
1.244 dtucker 2134: debug3("rekey after %llu bytes, %u seconds", (unsigned long long)bytes,
2135: (unsigned int)seconds);
1.201 markus 2136: ssh->state->rekey_limit = bytes;
2137: ssh->state->rekey_interval = seconds;
1.184 dtucker 2138: }
2139:
2140: time_t
1.201 markus 2141: ssh_packet_get_rekey_timeout(struct ssh *ssh)
1.184 dtucker 2142: {
2143: time_t seconds;
2144:
1.201 markus 2145: seconds = ssh->state->rekey_time + ssh->state->rekey_interval -
1.187 dtucker 2146: monotime();
1.185 dtucker 2147: return (seconds <= 0 ? 1 : seconds);
1.118 markus 2148: }
2149:
2150: void
1.201 markus 2151: ssh_packet_set_server(struct ssh *ssh)
1.118 markus 2152: {
1.201 markus 2153: ssh->state->server_side = 1;
1.278 djm 2154: ssh->kex->server = 1; /* XXX unify? */
1.118 markus 2155: }
2156:
2157: void
1.201 markus 2158: ssh_packet_set_authenticated(struct ssh *ssh)
1.118 markus 2159: {
1.201 markus 2160: ssh->state->after_authentication = 1;
1.161 andreas 2161: }
2162:
2163: void *
1.201 markus 2164: ssh_packet_get_input(struct ssh *ssh)
1.161 andreas 2165: {
1.201 markus 2166: return (void *)ssh->state->input;
1.161 andreas 2167: }
2168:
2169: void *
1.201 markus 2170: ssh_packet_get_output(struct ssh *ssh)
1.161 andreas 2171: {
1.201 markus 2172: return (void *)ssh->state->output;
1.166 andreas 2173: }
2174:
1.196 markus 2175: /* Reset after_authentication and reset compression in post-auth privsep */
1.201 markus 2176: static int
2177: ssh_packet_set_postauth(struct ssh *ssh)
1.196 markus 2178: {
1.239 djm 2179: int r;
1.196 markus 2180:
1.297 djm 2181: debug_f("called");
1.196 markus 2182: /* This was set in net child, but is not visible in user child */
1.201 markus 2183: ssh->state->after_authentication = 1;
2184: ssh->state->rekeying = 0;
1.239 djm 2185: if ((r = ssh_packet_enable_delayed_compress(ssh)) != 0)
2186: return r;
1.201 markus 2187: return 0;
2188: }
2189:
2190: /* Packet state (de-)serialization for privsep */
2191:
2192: /* turn kex into a blob for packet state serialization */
2193: static int
2194: kex_to_blob(struct sshbuf *m, struct kex *kex)
2195: {
2196: int r;
2197:
1.299 djm 2198: if ((r = sshbuf_put_u32(m, kex->we_need)) != 0 ||
1.269 djm 2199: (r = sshbuf_put_cstring(m, kex->hostkey_alg)) != 0 ||
1.201 markus 2200: (r = sshbuf_put_u32(m, kex->hostkey_type)) != 0 ||
1.269 djm 2201: (r = sshbuf_put_u32(m, kex->hostkey_nid)) != 0 ||
1.201 markus 2202: (r = sshbuf_put_u32(m, kex->kex_type)) != 0 ||
1.309.4.1! bluhm 2203: (r = sshbuf_put_u32(m, kex->kex_strict)) != 0 ||
1.201 markus 2204: (r = sshbuf_put_stringb(m, kex->my)) != 0 ||
2205: (r = sshbuf_put_stringb(m, kex->peer)) != 0 ||
1.278 djm 2206: (r = sshbuf_put_stringb(m, kex->client_version)) != 0 ||
2207: (r = sshbuf_put_stringb(m, kex->server_version)) != 0 ||
1.299 djm 2208: (r = sshbuf_put_stringb(m, kex->session_id)) != 0 ||
1.278 djm 2209: (r = sshbuf_put_u32(m, kex->flags)) != 0)
1.201 markus 2210: return r;
2211: return 0;
2212: }
2213:
2214: /* turn key exchange results into a blob for packet state serialization */
2215: static int
2216: newkeys_to_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2217: {
2218: struct sshbuf *b;
2219: struct sshcipher_ctx *cc;
2220: struct sshcomp *comp;
2221: struct sshenc *enc;
2222: struct sshmac *mac;
2223: struct newkeys *newkey;
2224: int r;
2225:
2226: if ((newkey = ssh->state->newkeys[mode]) == NULL)
2227: return SSH_ERR_INTERNAL_ERROR;
2228: enc = &newkey->enc;
2229: mac = &newkey->mac;
2230: comp = &newkey->comp;
1.235 djm 2231: cc = (mode == MODE_OUT) ? ssh->state->send_context :
2232: ssh->state->receive_context;
1.201 markus 2233: if ((r = cipher_get_keyiv(cc, enc->iv, enc->iv_len)) != 0)
2234: return r;
2235: if ((b = sshbuf_new()) == NULL)
2236: return SSH_ERR_ALLOC_FAIL;
2237: if ((r = sshbuf_put_cstring(b, enc->name)) != 0 ||
2238: (r = sshbuf_put_u32(b, enc->enabled)) != 0 ||
2239: (r = sshbuf_put_u32(b, enc->block_size)) != 0 ||
2240: (r = sshbuf_put_string(b, enc->key, enc->key_len)) != 0 ||
2241: (r = sshbuf_put_string(b, enc->iv, enc->iv_len)) != 0)
2242: goto out;
2243: if (cipher_authlen(enc->cipher) == 0) {
2244: if ((r = sshbuf_put_cstring(b, mac->name)) != 0 ||
2245: (r = sshbuf_put_u32(b, mac->enabled)) != 0 ||
2246: (r = sshbuf_put_string(b, mac->key, mac->key_len)) != 0)
2247: goto out;
2248: }
2249: if ((r = sshbuf_put_u32(b, comp->type)) != 0 ||
2250: (r = sshbuf_put_cstring(b, comp->name)) != 0)
2251: goto out;
2252: r = sshbuf_put_stringb(m, b);
2253: out:
1.221 mmcc 2254: sshbuf_free(b);
1.201 markus 2255: return r;
2256: }
2257:
2258: /* serialize packet state into a blob */
2259: int
2260: ssh_packet_get_state(struct ssh *ssh, struct sshbuf *m)
2261: {
2262: struct session_state *state = ssh->state;
1.249 djm 2263: int r;
1.201 markus 2264:
1.249 djm 2265: if ((r = kex_to_blob(m, ssh->kex)) != 0 ||
2266: (r = newkeys_to_blob(m, ssh, MODE_OUT)) != 0 ||
2267: (r = newkeys_to_blob(m, ssh, MODE_IN)) != 0 ||
2268: (r = sshbuf_put_u64(m, state->rekey_limit)) != 0 ||
2269: (r = sshbuf_put_u32(m, state->rekey_interval)) != 0 ||
2270: (r = sshbuf_put_u32(m, state->p_send.seqnr)) != 0 ||
2271: (r = sshbuf_put_u64(m, state->p_send.blocks)) != 0 ||
2272: (r = sshbuf_put_u32(m, state->p_send.packets)) != 0 ||
2273: (r = sshbuf_put_u64(m, state->p_send.bytes)) != 0 ||
2274: (r = sshbuf_put_u32(m, state->p_read.seqnr)) != 0 ||
2275: (r = sshbuf_put_u64(m, state->p_read.blocks)) != 0 ||
2276: (r = sshbuf_put_u32(m, state->p_read.packets)) != 0 ||
1.255 djm 2277: (r = sshbuf_put_u64(m, state->p_read.bytes)) != 0 ||
2278: (r = sshbuf_put_stringb(m, state->input)) != 0 ||
2279: (r = sshbuf_put_stringb(m, state->output)) != 0)
1.256 djm 2280: return r;
1.201 markus 2281:
2282: return 0;
2283: }
2284:
2285: /* restore key exchange results from blob for packet state de-serialization */
2286: static int
2287: newkeys_from_blob(struct sshbuf *m, struct ssh *ssh, int mode)
2288: {
2289: struct sshbuf *b = NULL;
2290: struct sshcomp *comp;
2291: struct sshenc *enc;
2292: struct sshmac *mac;
2293: struct newkeys *newkey = NULL;
2294: size_t keylen, ivlen, maclen;
2295: int r;
2296:
2297: if ((newkey = calloc(1, sizeof(*newkey))) == NULL) {
2298: r = SSH_ERR_ALLOC_FAIL;
2299: goto out;
2300: }
2301: if ((r = sshbuf_froms(m, &b)) != 0)
2302: goto out;
2303: #ifdef DEBUG_PK
2304: sshbuf_dump(b, stderr);
2305: #endif
2306: enc = &newkey->enc;
2307: mac = &newkey->mac;
2308: comp = &newkey->comp;
2309:
2310: if ((r = sshbuf_get_cstring(b, &enc->name, NULL)) != 0 ||
2311: (r = sshbuf_get_u32(b, (u_int *)&enc->enabled)) != 0 ||
2312: (r = sshbuf_get_u32(b, &enc->block_size)) != 0 ||
2313: (r = sshbuf_get_string(b, &enc->key, &keylen)) != 0 ||
2314: (r = sshbuf_get_string(b, &enc->iv, &ivlen)) != 0)
2315: goto out;
1.262 djm 2316: if ((enc->cipher = cipher_by_name(enc->name)) == NULL) {
2317: r = SSH_ERR_INVALID_FORMAT;
2318: goto out;
2319: }
1.201 markus 2320: if (cipher_authlen(enc->cipher) == 0) {
2321: if ((r = sshbuf_get_cstring(b, &mac->name, NULL)) != 0)
2322: goto out;
2323: if ((r = mac_setup(mac, mac->name)) != 0)
2324: goto out;
2325: if ((r = sshbuf_get_u32(b, (u_int *)&mac->enabled)) != 0 ||
2326: (r = sshbuf_get_string(b, &mac->key, &maclen)) != 0)
2327: goto out;
2328: if (maclen > mac->key_len) {
2329: r = SSH_ERR_INVALID_FORMAT;
2330: goto out;
2331: }
2332: mac->key_len = maclen;
2333: }
2334: if ((r = sshbuf_get_u32(b, &comp->type)) != 0 ||
2335: (r = sshbuf_get_cstring(b, &comp->name, NULL)) != 0)
2336: goto out;
2337: if (sshbuf_len(b) != 0) {
2338: r = SSH_ERR_INVALID_FORMAT;
2339: goto out;
2340: }
2341: enc->key_len = keylen;
2342: enc->iv_len = ivlen;
2343: ssh->kex->newkeys[mode] = newkey;
2344: newkey = NULL;
2345: r = 0;
2346: out:
1.219 mmcc 2347: free(newkey);
1.221 mmcc 2348: sshbuf_free(b);
1.201 markus 2349: return r;
2350: }
2351:
2352: /* restore kex from blob for packet state de-serialization */
2353: static int
2354: kex_from_blob(struct sshbuf *m, struct kex **kexp)
2355: {
2356: struct kex *kex;
2357: int r;
2358:
1.278 djm 2359: if ((kex = kex_new()) == NULL)
2360: return SSH_ERR_ALLOC_FAIL;
1.299 djm 2361: if ((r = sshbuf_get_u32(m, &kex->we_need)) != 0 ||
1.269 djm 2362: (r = sshbuf_get_cstring(m, &kex->hostkey_alg, NULL)) != 0 ||
1.201 markus 2363: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_type)) != 0 ||
1.269 djm 2364: (r = sshbuf_get_u32(m, (u_int *)&kex->hostkey_nid)) != 0 ||
1.201 markus 2365: (r = sshbuf_get_u32(m, &kex->kex_type)) != 0 ||
1.309.4.1! bluhm 2366: (r = sshbuf_get_u32(m, &kex->kex_strict)) != 0 ||
1.201 markus 2367: (r = sshbuf_get_stringb(m, kex->my)) != 0 ||
2368: (r = sshbuf_get_stringb(m, kex->peer)) != 0 ||
1.278 djm 2369: (r = sshbuf_get_stringb(m, kex->client_version)) != 0 ||
2370: (r = sshbuf_get_stringb(m, kex->server_version)) != 0 ||
1.299 djm 2371: (r = sshbuf_get_stringb(m, kex->session_id)) != 0 ||
1.278 djm 2372: (r = sshbuf_get_u32(m, &kex->flags)) != 0)
1.201 markus 2373: goto out;
2374: kex->server = 1;
2375: kex->done = 1;
2376: r = 0;
2377: out:
2378: if (r != 0 || kexp == NULL) {
1.278 djm 2379: kex_free(kex);
1.201 markus 2380: if (kexp != NULL)
2381: *kexp = NULL;
2382: } else {
1.278 djm 2383: kex_free(*kexp);
1.201 markus 2384: *kexp = kex;
2385: }
2386: return r;
2387: }
2388:
2389: /*
2390: * Restore packet state from content of blob 'm' (de-serialization).
2391: * Note that 'm' will be partially consumed on parsing or any other errors.
2392: */
2393: int
2394: ssh_packet_set_state(struct ssh *ssh, struct sshbuf *m)
2395: {
2396: struct session_state *state = ssh->state;
1.254 djm 2397: const u_char *input, *output;
2398: size_t ilen, olen;
1.201 markus 2399: int r;
2400:
1.249 djm 2401: if ((r = kex_from_blob(m, &ssh->kex)) != 0 ||
2402: (r = newkeys_from_blob(m, ssh, MODE_OUT)) != 0 ||
2403: (r = newkeys_from_blob(m, ssh, MODE_IN)) != 0 ||
2404: (r = sshbuf_get_u64(m, &state->rekey_limit)) != 0 ||
2405: (r = sshbuf_get_u32(m, &state->rekey_interval)) != 0 ||
2406: (r = sshbuf_get_u32(m, &state->p_send.seqnr)) != 0 ||
2407: (r = sshbuf_get_u64(m, &state->p_send.blocks)) != 0 ||
2408: (r = sshbuf_get_u32(m, &state->p_send.packets)) != 0 ||
2409: (r = sshbuf_get_u64(m, &state->p_send.bytes)) != 0 ||
2410: (r = sshbuf_get_u32(m, &state->p_read.seqnr)) != 0 ||
2411: (r = sshbuf_get_u64(m, &state->p_read.blocks)) != 0 ||
2412: (r = sshbuf_get_u32(m, &state->p_read.packets)) != 0 ||
2413: (r = sshbuf_get_u64(m, &state->p_read.bytes)) != 0)
2414: return r;
2415: /*
1.296 djm 2416: * We set the time here so that in post-auth privsep child we
1.249 djm 2417: * count from the completion of the authentication.
2418: */
2419: state->rekey_time = monotime();
2420: /* XXX ssh_set_newkeys overrides p_read.packets? XXX */
2421: if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0 ||
2422: (r = ssh_set_newkeys(ssh, MODE_OUT)) != 0)
2423: return r;
1.201 markus 2424:
1.239 djm 2425: if ((r = ssh_packet_set_postauth(ssh)) != 0)
1.201 markus 2426: return r;
2427:
2428: sshbuf_reset(state->input);
2429: sshbuf_reset(state->output);
2430: if ((r = sshbuf_get_string_direct(m, &input, &ilen)) != 0 ||
2431: (r = sshbuf_get_string_direct(m, &output, &olen)) != 0 ||
2432: (r = sshbuf_put(state->input, input, ilen)) != 0 ||
2433: (r = sshbuf_put(state->output, output, olen)) != 0)
2434: return r;
2435:
2436: if (sshbuf_len(m))
2437: return SSH_ERR_INVALID_FORMAT;
1.297 djm 2438: debug3_f("done");
1.201 markus 2439: return 0;
2440: }
2441:
2442: /* NEW API */
2443:
2444: /* put data to the outgoing packet */
2445:
2446: int
2447: sshpkt_put(struct ssh *ssh, const void *v, size_t len)
2448: {
2449: return sshbuf_put(ssh->state->outgoing_packet, v, len);
2450: }
2451:
2452: int
2453: sshpkt_putb(struct ssh *ssh, const struct sshbuf *b)
2454: {
2455: return sshbuf_putb(ssh->state->outgoing_packet, b);
2456: }
2457:
2458: int
2459: sshpkt_put_u8(struct ssh *ssh, u_char val)
2460: {
2461: return sshbuf_put_u8(ssh->state->outgoing_packet, val);
2462: }
2463:
2464: int
2465: sshpkt_put_u32(struct ssh *ssh, u_int32_t val)
2466: {
2467: return sshbuf_put_u32(ssh->state->outgoing_packet, val);
2468: }
2469:
2470: int
2471: sshpkt_put_u64(struct ssh *ssh, u_int64_t val)
2472: {
2473: return sshbuf_put_u64(ssh->state->outgoing_packet, val);
2474: }
2475:
2476: int
2477: sshpkt_put_string(struct ssh *ssh, const void *v, size_t len)
2478: {
2479: return sshbuf_put_string(ssh->state->outgoing_packet, v, len);
2480: }
2481:
2482: int
2483: sshpkt_put_cstring(struct ssh *ssh, const void *v)
2484: {
2485: return sshbuf_put_cstring(ssh->state->outgoing_packet, v);
2486: }
2487:
2488: int
2489: sshpkt_put_stringb(struct ssh *ssh, const struct sshbuf *v)
2490: {
2491: return sshbuf_put_stringb(ssh->state->outgoing_packet, v);
2492: }
2493:
1.211 djm 2494: #ifdef WITH_OPENSSL
1.201 markus 2495: int
2496: sshpkt_put_ec(struct ssh *ssh, const EC_POINT *v, const EC_GROUP *g)
2497: {
2498: return sshbuf_put_ec(ssh->state->outgoing_packet, v, g);
2499: }
2500:
2501:
2502: int
2503: sshpkt_put_bignum2(struct ssh *ssh, const BIGNUM *v)
2504: {
2505: return sshbuf_put_bignum2(ssh->state->outgoing_packet, v);
2506: }
1.211 djm 2507: #endif /* WITH_OPENSSL */
1.201 markus 2508:
2509: /* fetch data from the incoming packet */
2510:
2511: int
2512: sshpkt_get(struct ssh *ssh, void *valp, size_t len)
2513: {
2514: return sshbuf_get(ssh->state->incoming_packet, valp, len);
2515: }
2516:
2517: int
2518: sshpkt_get_u8(struct ssh *ssh, u_char *valp)
2519: {
2520: return sshbuf_get_u8(ssh->state->incoming_packet, valp);
2521: }
2522:
2523: int
2524: sshpkt_get_u32(struct ssh *ssh, u_int32_t *valp)
2525: {
2526: return sshbuf_get_u32(ssh->state->incoming_packet, valp);
2527: }
2528:
2529: int
2530: sshpkt_get_u64(struct ssh *ssh, u_int64_t *valp)
2531: {
2532: return sshbuf_get_u64(ssh->state->incoming_packet, valp);
2533: }
2534:
2535: int
2536: sshpkt_get_string(struct ssh *ssh, u_char **valp, size_t *lenp)
2537: {
2538: return sshbuf_get_string(ssh->state->incoming_packet, valp, lenp);
2539: }
2540:
2541: int
2542: sshpkt_get_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2543: {
2544: return sshbuf_get_string_direct(ssh->state->incoming_packet, valp, lenp);
2545: }
2546:
2547: int
1.264 djm 2548: sshpkt_peek_string_direct(struct ssh *ssh, const u_char **valp, size_t *lenp)
2549: {
2550: return sshbuf_peek_string_direct(ssh->state->incoming_packet, valp, lenp);
2551: }
2552:
2553: int
1.201 markus 2554: sshpkt_get_cstring(struct ssh *ssh, char **valp, size_t *lenp)
2555: {
2556: return sshbuf_get_cstring(ssh->state->incoming_packet, valp, lenp);
1.282 djm 2557: }
2558:
2559: int
2560: sshpkt_getb_froms(struct ssh *ssh, struct sshbuf **valp)
2561: {
2562: return sshbuf_froms(ssh->state->incoming_packet, valp);
1.201 markus 2563: }
2564:
1.211 djm 2565: #ifdef WITH_OPENSSL
1.201 markus 2566: int
2567: sshpkt_get_ec(struct ssh *ssh, EC_POINT *v, const EC_GROUP *g)
2568: {
2569: return sshbuf_get_ec(ssh->state->incoming_packet, v, g);
2570: }
2571:
2572: int
1.281 djm 2573: sshpkt_get_bignum2(struct ssh *ssh, BIGNUM **valp)
1.201 markus 2574: {
1.281 djm 2575: return sshbuf_get_bignum2(ssh->state->incoming_packet, valp);
1.201 markus 2576: }
1.211 djm 2577: #endif /* WITH_OPENSSL */
1.201 markus 2578:
2579: int
2580: sshpkt_get_end(struct ssh *ssh)
2581: {
2582: if (sshbuf_len(ssh->state->incoming_packet) > 0)
2583: return SSH_ERR_UNEXPECTED_TRAILING_DATA;
2584: return 0;
2585: }
2586:
2587: const u_char *
2588: sshpkt_ptr(struct ssh *ssh, size_t *lenp)
2589: {
2590: if (lenp != NULL)
2591: *lenp = sshbuf_len(ssh->state->incoming_packet);
2592: return sshbuf_ptr(ssh->state->incoming_packet);
2593: }
2594:
2595: /* start a new packet */
2596:
2597: int
2598: sshpkt_start(struct ssh *ssh, u_char type)
2599: {
1.249 djm 2600: u_char buf[6]; /* u32 packet length, u8 pad len, u8 type */
1.201 markus 2601:
2602: DBG(debug("packet_start[%d]", type));
1.249 djm 2603: memset(buf, 0, sizeof(buf));
2604: buf[sizeof(buf) - 1] = type;
1.201 markus 2605: sshbuf_reset(ssh->state->outgoing_packet);
1.249 djm 2606: return sshbuf_put(ssh->state->outgoing_packet, buf, sizeof(buf));
1.201 markus 2607: }
2608:
1.242 markus 2609: static int
2610: ssh_packet_send_mux(struct ssh *ssh)
2611: {
2612: struct session_state *state = ssh->state;
2613: u_char type, *cp;
2614: size_t len;
2615: int r;
2616:
2617: if (ssh->kex)
2618: return SSH_ERR_INTERNAL_ERROR;
2619: len = sshbuf_len(state->outgoing_packet);
2620: if (len < 6)
2621: return SSH_ERR_INTERNAL_ERROR;
2622: cp = sshbuf_mutable_ptr(state->outgoing_packet);
2623: type = cp[5];
2624: if (ssh_packet_log_type(type))
1.297 djm 2625: debug3_f("type %u", type);
1.242 markus 2626: /* drop everything, but the connection protocol */
2627: if (type >= SSH2_MSG_CONNECTION_MIN &&
2628: type <= SSH2_MSG_CONNECTION_MAX) {
2629: POKE_U32(cp, len - 4);
2630: if ((r = sshbuf_putb(state->output,
2631: state->outgoing_packet)) != 0)
2632: return r;
2633: /* sshbuf_dump(state->output, stderr); */
2634: }
2635: sshbuf_reset(state->outgoing_packet);
1.264 djm 2636: return 0;
2637: }
2638:
2639: /*
2640: * 9.2. Ignored Data Message
2641: *
2642: * byte SSH_MSG_IGNORE
2643: * string data
2644: *
2645: * All implementations MUST understand (and ignore) this message at any
2646: * time (after receiving the protocol version). No implementation is
2647: * required to send them. This message can be used as an additional
2648: * protection measure against advanced traffic analysis techniques.
2649: */
2650: int
2651: sshpkt_msg_ignore(struct ssh *ssh, u_int nbytes)
2652: {
2653: u_int32_t rnd = 0;
2654: int r;
2655: u_int i;
2656:
2657: if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
2658: (r = sshpkt_put_u32(ssh, nbytes)) != 0)
2659: return r;
2660: for (i = 0; i < nbytes; i++) {
2661: if (i % 4 == 0)
2662: rnd = arc4random();
2663: if ((r = sshpkt_put_u8(ssh, (u_char)rnd & 0xff)) != 0)
2664: return r;
2665: rnd >>= 8;
2666: }
1.242 markus 2667: return 0;
2668: }
2669:
1.201 markus 2670: /* send it */
2671:
2672: int
2673: sshpkt_send(struct ssh *ssh)
2674: {
1.242 markus 2675: if (ssh->state && ssh->state->mux)
2676: return ssh_packet_send_mux(ssh);
1.249 djm 2677: return ssh_packet_send2(ssh);
1.201 markus 2678: }
2679:
2680: int
2681: sshpkt_disconnect(struct ssh *ssh, const char *fmt,...)
2682: {
2683: char buf[1024];
2684: va_list args;
2685: int r;
2686:
2687: va_start(args, fmt);
2688: vsnprintf(buf, sizeof(buf), fmt, args);
2689: va_end(args);
2690:
1.309.4.1! bluhm 2691: debug2_f("sending SSH2_MSG_DISCONNECT: %s", buf);
1.249 djm 2692: if ((r = sshpkt_start(ssh, SSH2_MSG_DISCONNECT)) != 0 ||
2693: (r = sshpkt_put_u32(ssh, SSH2_DISCONNECT_PROTOCOL_ERROR)) != 0 ||
2694: (r = sshpkt_put_cstring(ssh, buf)) != 0 ||
2695: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
2696: (r = sshpkt_send(ssh)) != 0)
2697: return r;
1.201 markus 2698: return 0;
2699: }
2700:
2701: /* roundup current message to pad bytes */
2702: int
2703: sshpkt_add_padding(struct ssh *ssh, u_char pad)
2704: {
2705: ssh->state->extra_pad = pad;
2706: return 0;
1.1 deraadt 2707: }